
A man led by horrific visions to a mysterious cabin hopes to put a stop to his nightmares. An H.P. Lovecraft inspired film.
Does Harbinger have end credit scenes?
No!
Harbinger does not have end credit scenes. You can leave when the credits roll.
Explore the complete cast of Harbinger, including both lead and supporting actors. Learn who plays each character, discover their past roles and achievements, and find out what makes this ensemble cast stand out in the world of film and television.
Discover where to watch Harbinger online, including streaming platforms, rental options, and official sources. Compare reviews, ratings, and in-depth movie information across sites like IMDb, TMDb, Wikipedia or Rotten Tomatoes.
Read the complete plot summary of Harbinger, including all major events, twists, and the full ending explained in detail. Explore key characters, themes, hidden meanings, and everything you need to understand the story from beginning to end.
In 1982, a Soviet moon lander crashes into the frigid Bering Sea, setting off a mystery that will resurface decades later. Fast forward to 2015, and biology professor Stephen and his graduate students Ronelle and Sadie join an experimental sea voyage to study how warming oceans affect whale populations. They ride out with Sadie’s grandfather, Graff, aboard his weathered fishing trawler, the Harbinger, which is crewed by the sturdy hands of Bowman, Roland, Big G, Dock, Svetlana, and Atka. The journey blends scientific curiosity with the rough-and-tumble life at sea, where every creak of the hull seems to carry a new clue.
One night, Sadie is roused by the crew’s activity and the ship’s sonar picks up anomalous whale signals in the area. She awakens the others and, with their help, she helps locate and recover the ice-encased lander. The discovery triggers a conflict: Stephen immediately asserts ownership, but Graff counters that the find should belong to Sadie, who discovered it first. Bowman pushes Sadie to investigate before Stephen can seize the discovery for his prestige or career. As Big G distracts Stephen, Sadie carefully examines the lander and uncovers the body of a cosmonaut, who apparently died from an unknown infection, and she collects a skin sample to study later. The tension rises when Stephen learns that Sadie had already examined the lander, and he threatens to ruin her career unless she signs over the discovery to him. Graff warns of legal action, but Sadie finally yields. She soon learns the lander carried tardigrades, hardy organisms capable of surviving extreme conditions; but a cosmic radiation exposure has mutated them into something far more dangerous and capable of shapeshifting.
When the cosmonaut’s body goes missing, Stephen’s curiosity turns to contamination as he examines the lander and becomes infected by the tardigrades. The reanimated cosmonaut’s body kills Roland, and Stephen, chilled to the bone, strips on deck in the sub-zero air before the others pull him back inside. Dark, lifelike growths sprout from his back and spray a murky liquid over the crew. Sadie confirms that the entire party could be contaminated. The group freezes Stephen’s body and the lander using liquid nitrogen to halt their spread.
As Dock begins showing signs of infection, Svetlana locks him in a cage and plans to incinerate him, but the situation escalates when Dock also sprouts tentacle-like growths. The ship’s power is knocked out, and the backup battery surges to life just as the crew fights to stabilize the vessel. The organism proves deadly again when it kills Atka, and Svetlana’s true allegiance is revealed: she is a Russian spy. She explains that the tardigrades were part of a Soviet experiment to create radiation-resistant cosmonauts and reveals a plan to sink the Harbinger after they board a nearby Russian submarine. Before she can carry out her plan, the organism lashes out, dragging Ronelle and Svetlana away.
In the wake of the attack, Graff, Sadie, Bowman, and Big G search for Svetlana’s hidden explosive charges scattered around the boat. The last of the charges lie in the cramped bilge, a space Sadie alone can access. As they collect the ordnance, the others learn that the tardigrades have eaten and absorbed their last catch—two tons of crab—heightening the danger. Sadie realizes she is now standing in the midst of a living swarm and narrowly escapes, but Graff becomes infected. He urges Big G to restart the boat and asks Sadie to take the helm, then tells Bowman to kill him to prevent further suffering.
Big G attempts the restart but is killed by the mutated Svetlana. Before Bowman can freeze Graff with liquid nitrogen, the creature strikes, impaling Bowman. Graff, in his final act, urges Sadie to scuttle the ship and save herself. She steers the Harbinger toward an approaching iceberg and escapes, while the organism bursts through the deck behind her. Through a portable radio, the US Coast Guard relays that a rescue helicopter is closing in. Sadie, exhausted and battered, collapses onto the ice as the rotor blades shimmer on the horizon, and she slips into unconsciousness, the Harbinger’s peril finally giving way to a fragile hope of rescue.
Uncover the Details: Timeline, Characters, Themes, and Beyond!

Coming soon on iOS and Android
From blockbusters to hidden gems — dive into movie stories anytime, anywhere. Save your favorites, discover plots faster, and never miss a twist again.
Sign up to be the first to know when we launch. Your email stays private — always.
Immerse yourself in the magic of cinema with live orchestral performances of your favorite film scores. From sweeping Hollywood blockbusters and animated classics to epic fantasy soundtracks, our curated listings connect you to upcoming film music events worldwide.
Explore concert film screenings paired with full orchestra concerts, read detailed event information, and secure your tickets for unforgettable evenings celebrating legendary composers like John Williams, Hans Zimmer, and more.
Explore all cars featured in Harbinger, including their makes, models, scenes they appear in, and their significance to the plot. A must-read for car enthusiasts and movie buffs alike.
Dive into our Movie Wiki for in-depth film encyclopedia entries, including cast biographies, production trivia, plot synopses, behind-the-scenes facts, and thematic analyses. Whether you’re researching iconic directors, exploring genre histories, or discovering hidden easter eggs, our expertly curated movie database has everything you need to fuel your cinematic passion.
What's After the Movie?
Not sure whether to stay after the credits? Find out!
Explore Our Movie Platform
New Movie Releases (2025)
Famous Movie Actors
Top Film Production Studios
Movie Plot Summaries & Endings
Major Movie Awards & Winners
Best Concert Films & Music Documentaries
Movie Collections and Curated Lists
© 2025 What's After the Movie. All rights reserved.