What Is Parts Per Billion About?
The premise of Parts Per Billion in 284 words, with nothing given away. The full story follows below.
In a world teetering on the brink of collapse, a relentless war has pushed humanity into a fragile limbo where every breath feels borrowed. The looming threat of a human‑made biological disaster casts a pall over everyday life, turning ordinary streets into corridors of whispered fear. Against this backdrop, the film unfolds as a quiet, tension‑laden meditation on how love and survival intersect when the future itself is uncertain.
Len is a once‑promising writer now adrift, wrestling with a sense of purposelessness that has begun to seep into his marriage. His partner, Mia, a sharp‑tongued lawyer, balances her career’s demands with the lingering ache of having taken her husband for granted. Their interactions reveal a marriage caught between lingering affection and the weight of unspoken regrets, each conversation a tightrope between hope and resignation.
Erik lives in the shadow of his family’s wealth, channeling his restless energy into music while trying to prove his independence. His relationship with Anna is marked by a mixture of tenderness and friction, as she oscillates between yearning for deeper connection and grappling with unsettling visions that hint at something far larger than their personal concerns. Their dynamic paints a portrait of youthful passion strained by the world’s encroaching dread.
Andy carries the legacy of his scientific past, haunted by the ethical shadows of his work, while his wife Esther embodies quiet optimism that clings to the possibility of redemption. Their partnership illustrates a generational perspective on responsibility and the moral compromises made in the name of survival. Together, these three couples navigate an atmosphere thick with anxiety, each confronting choices that test the limits of their devotion, resilience, and humanity as the world around them threatens to unravel.
What Happens in Parts Per Billion?
The complete story of Parts Per Billion, from the first scene to the last, in 846 words (about 4 minutes). Spoilers throughout. Names in the text link to 7 cast member pages.
Spoilers ahead
Anna, Teresa Palmer, and Erik, Penn Badgley, are a wealthy, music-loving couple whose days are cushioned by Erik’s family fortune. Erik is a struggling musician more focused on his craft and keeping amicable ties with his exes than on the couple’s day-to-day life, while Anna grows increasingly anxious about the fragility of their seemingly comfortable existence. They clash over seemingly trivial details, yet the undercurrent of unease grows as Anna watches headlines about escalating conflicts in the Middle East. She begins to believe they should spend more time together, to anchor themselves against a world that feels increasingly volatile. But Erik drifts toward his composition and his social circles, and the distance between them widens, masking deeper fears with casual routines and shared, but shallow, routines.
Len, Josh Hartnett, is a depressed and unemployed writer whose life has lost direction, and Mia, Rosario Dawson, his wife and a capable lawyer, finds herself navigating a demanding career and a strained marriage at once. Their relationship rides an uneasy line as Len threads through his own insecurities, while Mia’s professional successes clash with personal stress. Len confesses to his sister, a nurse named Sarah, Nazneen Contractor, that he has taken Mia for granted and longs for a sense of purpose again. Mia, meanwhile, has just won a significant case representing Andy, a scientist of some renown, who is accused of selling trade secrets to a research facility in the 1970s. The news of Mia’s victory sits alongside Len’s quiet despair, painting a portrait of two couples moving through parallel yet divergent struggles.
Andy, Erik’s grandfather, Frank Langella, pushes Erik to take more money, insisting that the family’s wealth could be a safety net—or a burden. Erik refuses, determined to prove he can make it on his own, a choice that sparks a misunderstanding with Andy, who accuses him of being patronized by the legacy of wealth. Esther, Andy’s wife, Gena Rowlands, is more forgiving about the past, arguing that the money preserved a future for their daughter when the stakes were at their highest. She remains an eternal optimist, believing in a life beyond the immediate crisis, while Andy, a realist, temperatures his optimism with a sobering awareness of ethical gray areas in their history. As the world outside spirals, their family’s finances and loyalties become entangled in a web of memory, guilt, and survival.
Across the globe, tensions flare into a dangerous reality. Biological weapons are at first rumored to be deployed, then confirmed, and the United States urges calm while Europe reels from casualties as toxins drift west with the trade winds. The looming possibility of catastrophe pushes both families toward the edge. In a moment of practical fear, Sarah alerts Len, who then escorts Mia into their basement to shield them from the chaos as the phone lines fail and panic spreads. Rick, a determined survivalist, attempts to purchase a survival kit but cannot secure the funds in time; he is shot by a looter when his desperation outpaces his luck. The city’s anxiety becomes a palpable presence, a character in its own right, as people scramble for safety and scarce resources.
Back at home, Erik and Anna endure their own trial by silence. Andy and Esther survive the worst of the crisis by relying on oxygen tanks, a small lifeline in a world where every breath feels like a choice. Esther remains stubbornly hopeful that Erik and Anna have endured somehow, while Andy remains a realist who doubts their survival. Through flashbacks interwoven with their arguments, we glimpse Erik and Anna’s carefree early days—flirtations, intimacy, and the news of Anna’s pregnancy—moments that make the present crisis feel more personal and intimate. The flashbacks culminate in a stark image: the apparent deaths of Erik and Anna as they lie together, never fully knowing whether they will wake or see tomorrow.
In the present, Esther awakens to the grim reality of the hospital’s oxygen hunt while Andy pushes forward, determined to secure life in the face of overwhelming odds. They uncover Sarah’s body during a hospital run and are sobered by the loss of life that surrounds them. Esther’s spirit wavers, but Andy’s quiet resolve reminds her that they still have each other. The two lovers, Len and Mia, stand at a precipice in their own relationship: Mia admits a painful failure to protect a coworker who fell in love with her, and Len, wounded, implores her to stay and to fight for their chance at rebuilding a life together. They reconcile just enough to hold on, even as the world outside continues to turn toward an uncertain dawn.
The film’s final image centers on a haunting, almost mythic note: a young girl—one of the visions Anna has carried—discovers Anna’s ring and presents it to her mother. It’s a fragile, hopeful connection to a life that remains beyond the immediate danger, a spark that hints at renewed faith in tomorrow even as the present remains perilous. The story closes with a quiet sense that, despite the losses and near-misses, small moments of grace and resilience persist.
Parts Per Billion Timeline: Every Key Event in Order
13 key events in the order they happen, from “Anna and Erik's uneasy comfort” to “A glimmer of hope through a vision”. 13 events name a place, across 12 locations.
- 1
Anna and Erik's uneasy comfort
Anna and Erik live a life cushioned by wealth, yet Anna grows anxious about how fragile their comfort feels. They clash over seemingly trivial details as Middle East headlines loom in the background. The tension pushes them to seek a shared anchor even as unease grows.
When:Present day Where:Their home
- 2
Erik drifts toward his music and circles
Erik pours himself into composing and his social circle, often at the expense of the couple's day-to-day life. The distance between him and Anna widens despite their ongoing routines. He struggles to reconcile his artistic ambition with the relationship’s needs.
When:Present Where:Erik's home and social circle
- 3
Len confesses to his sister
Len, depressed and unemployed, confesses to his sister Sarah that he has taken Mia for granted and longs for purpose again. Sarah, a nurse, offers practical support as she listens. The admission underscores the strain rippling through both couples.
When:Present Where:Len's apartment
- 4
Mia wins a significant case
Mia, a capable lawyer, wins a significant case representing Andy, a scientist accused of selling trade secrets. The victory highlights Mia's professional success in contrast to Len's growing despair. The moment intensifies the tension between personal and professional pressures.
When:Present Where:Courtroom
- 5
Erik faces family pressure about wealth
Andy's insistence that Erik rely on the family wealth creates a clash, with Erik insisting he wants to prove himself independently. Esther argues the money can be a safeguard, while Andy remains wary of how wealth shapes loyalties. The exchange deepens the rift between generations and sharpens the looming financial strain.
When:Present Where:Family estate
- 6
Global tensions bleed into daily life
Biological weapons rumors turn to confirmation as the world teeters on the edge; the US urges calm while Europe suffers casualties and toxins drift west on the wind. The outside crisis bleeds into every home and conversation, heightening the sense of impending disaster.
Where:Global
- 7
Basement shelter and communication collapse
Sarah alerts Len, who escorts Mia into the basement to shield them from chaos as lines fail and panic spreads. The building's safety becomes the couple's immediate concern while the world outside spirals.
When:During crisis Where:Len and Mia's basement
- 8
Rick's desperate attempt ends in tragedy
Rick, a determined survivalist, tries to purchase a survival kit but cannot secure the funds in time, and is shot by a looter as desperation overwhelms the city. The incident underscores the brutal stakes of scarcity and fear.
When:During crisis Where:City
- 9
Erik and Anna's trial by silence
Back at home, Erik and Anna endure their crisis in tense silence; flashbacks reveal their carefree early days, flirtations, and Anna's pregnancy. The flashbacks culminate in a stark image of their apparent deaths, leaving the present unsettled.
When:Present with flashbacks Where:Home
- 10
Esther and Andy endure with oxygen
Esther awakens to the hospital's oxygen crisis while Andy pushes forward, relying on oxygen tanks as a lifeline in a world where every breath matters. Their bond tightens as they navigate the crisis together.
When:Present Where:Hospital
Show the other 3 events of Parts Per Billion Hide the last 3 events
- 11
Sarah's body found; hope tempered
During a hospital run, Esther and Andy uncover Sarah's body, a stark reminder of the toll the crisis has taken. The grim discovery sobers them, yet it also steels their resolve to endure.
When:Present Where:Hospital
- 12
Len and Mia confront fracture and choose to fight
Len, wounded by events, pleads with Mia to stay and fight for a future together. Mia admits she failed to protect a coworker who fell for her, and they tentatively decide to hold on and rebuild.
When:Present Where:Len and Mia's apartment
- 13
A glimmer of hope through a vision
A final image shows a young girl—one of Anna's visions—discovering Anna's ring and presenting it to her mother, a fragile spark of hope that life can continue beyond danger.
When:Final image Where:Unknown
Who Are the Main Characters in Parts Per Billion?
8 characters, among them Anna (Teresa Palmer), Erik (Penn Badgley) and Len (Josh Hartnett): who each one is and the part they play in the story. Every profile links to the actor’s page.
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Anna (Teresa Palmer)
Played by Teresa Palmer
A wealthy, music-loving wife who grows increasingly anxious about the fragility of her comfortable life. She clings to closeness with Erik as global turmoil intensifies, revealing a deeper fear of losing what she has built. Her pregnancy memories and intimate moments contrast with the external storm, highlighting vulnerability beneath privilege.
- 💎 Wealth
- 😟 Anxiety
- 💑 Relationship strain
-
Erik (Penn Badgley)
Played by Penn Badgley
A struggling musician in a world of family money, more focused on crafting his art and his social circle than on domestic life. He resists his grandfather’s pressure to accumulate wealth, a choice that strains family ties. Erik’s idealism clashes with practical realities as danger looms.
- 🎼 Music
- 🧭 Independence
- 🌀 Family tension
-
Len (Josh Hartnett)
Played by Josh Hartnett
A depressed and unemployed writer whose sense of purpose has withered, his marriage to Mia sits at a similar edge of fragility. He confesses his disconnection to his sister Sarah, revealing a longing for direction and meaning. Len’s personal crisis mirrors the larger world’s instability.
- 📚 Writer
- 😧 Depression
- 🌀 Isolation
-
Mia (Rosario Dawson)
Played by Rosario Dawson
A capable lawyer balancing a demanding career with a strained marriage. Mia’s recent victory for a scientist accused of misdeeds places her at the center of ethical and personal conflicts. She wrestles with protecting her relationship while managing professional success under pressure.
- ⚖️ Law
- 💼 Career
- 💪 Resilience
- S(
Sarah (Nazneen Contractor)
Played by Nazneen Contractor
Len’s sister, a nurse whose practical care underpins the family. She embodies nursing compassion amid chaos and becomes a conduit for family support as the crisis escalates. Her perspective anchors the human cost of the broader calamity.
- 💉 Nurse
- 👩👧 Family ties
- 🗣️ Communicator
-
Andy (Frank Langella)
Played by Frank Langella
Erik’s grandfather, a realist who anchors the family’s practical concerns. He pushes for more wealth as a safety net, yet he recognizes ethical gray areas in their history. His perspective contrasts with youthful idealism and underscores the tension between security and moral responsibility.
- 💰 Wealth
- 🧭 Realism
- 🔒 Family legacy
-
Esther (Gena Rowlands)
Played by Gena Rowlands
Andy’s wife, a hopeful presence who believes in a future beyond immediate danger. She navigates memory, loss, and the belief that love can endure when resources run scarce. Esther’s optimism acts as a counterweight to bleak external realities.
- 🌅 Hope
- ❤️ Family
- 🕊️ Forgiveness
-
Rick (Hill Harper)
Played by Hill Harper
A determined survivalist trying to secure a survival kit and protection in a world that feels increasingly unpredictable. His urgency and misfortune when funds fail him illustrate the scramble for basic safety. Rick embodies the desperation that accompanies scarcity.
- 🧰 Survivalist
- 🏃 Desperation
- 🗺️ Resource scarcity
Where and When Is Parts Per Billion Set?
Parts Per Billion is set in United States, Middle East and Europe (Present day with flashbacks to the 1970s). Here is why the time and place matter to the story.
When
Present day with flashbacks to the 1970s
The core action takes place in the contemporary era, reflecting current anxieties about conflict and biothreats. Flashbacks reveal a past era—the 1970s—where a scientist’s case about trade secrets influences present attitudes toward risk and wealth. The juxtaposition of past and present highlights how history informs character choices and family loyalties in a crisis.
Where
United States, Middle East, Europe
The story unfolds primarily in the United States within a privileged domestic sphere, then expands to a world where headlines threaten personal safety. The global crisis touches Europe and the Middle East, framing intimate drama against a backdrop of geopolitical tension. Urban homes, hospital corridors, basements, and public spaces become interconnected stages where fear and resilience collide.
- 🌍 Global context
- 🏙️ Urban life
- 🏥 Medical crisis
- 🧭 Survival stakes
What Are the Themes of Parts Per Billion?
4 ideas the story keeps returning to, among them Global Crisis, Relationship Strain and Ethics in Science.
-
01
Global Crisis
The film threads a personal narrative through a threatened world, showing how international tension infiltrates domestic life. Characters confront uncertainty as geopolitical events bleed into daily routines, forcing them to adapt quickly. The story suggests that private decisions can have public consequences when a world on edge bleeds into the home.
-
02
Relationship Strain
Wealth and privilege magnify insecurities within couples who clash over fear, safety, and priorities. The pressure of external danger exposes distance and miscommunication, turning small disagreements into tests of loyalty. Hope and attachment are put under strain as partners search for connection amid chaos.
-
03
Ethics in Science
A scientist's alleged illicit actions and the subsequent legal case raise questions about responsibility, money, and the moral boundaries of innovation. The narrative considers how scientific ambition intersects with personal gain and societal risk. It suggests that ethical choices are as crucial as technical prowess in a world fraught with danger.
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04
Memory and Resilience
Flashbacks to happier times contrast with the current peril, underscoring how memory sustains hope. The film frames small, intimate moments as acts of resilience against overwhelming odds. A final, symbolic image hints that grace and connection can outlive catastrophe, even when tomorrow remains uncertain.
What Kind of Film Is Parts Per Billion?
Dark in tone, with variable pacing and a moderate story, going by the plot summary.
- Tone
- Dark
- Pacing
- Variable
- Story
- Moderate
- Intensity
- High
- Ending
- Bittersweet
A foreboding and emotionally heavy drama that follows multiple couples through a devastating biological war, creating a melancholic atmosphere of anxiety and loss with a fragile undercurrent of hope.
- anxious
- melancholic
- bleak
- hopeful
- somber
- desperate
- apocalyptic survival
- strained relationships
- existential crisis
- war
Content notes: war violence, biological warfare, mass death, looting and civil unrest, character deaths.
Quiz
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