Doraemon: Nobita and the Steel Troops 1986

On a sunny playground, Suneo Honegawa Kaneta Kimotsuki flaunts his new radio-controlled toy robot, Micross. Watching in envy, Nobita Nobi Noriko Ohara rushes home to ask for a giant robot to outshine him. The ever-practical Doraemon Nobuyo Oyama refuses, and a heated argument pushes him to storm off through Doraemon’s Door to the North Pole. Nobita soon follows and stumbles upon a bowling-ball-sized mechanical orb that can summon the parts to assemble a massive robot.

Back home, Nobita and Doraemon decide to build the robot in an uninhabited mirror world reached by pouring Doraemon’s Opposite World Entrance Oil onto the surface of water. The finished machine appears to lack a brain, so Doraemon uses a psychic controller to pilot it. In the real world, Nobita’s mother accidentally trips on the orb and locks it away in a shed, delaying the project.

Nobita invites Shizuka Minamoto Michiko Nomura to join the game, and Doraemon names the robot “Zanda Cross” after finding it at the North Pole during their adventure with her. When Shizuka is handed the psychic controller to pilot it, she accidentally fires lasers at a skyscraper, destroying it and sending the group into a grave realization: Zanda Cross is a weapon of war. Realizing the potential consequences if such power escaped into the real world, they abandon both the robot and the mirror world, and vow never to speak of them again.

Meanwhile, a mysterious, scantily-clad girl named Lilulu begins tracking Zanda Cross all the way from the North Pole to Nobita’s world. She reveals that she is the true owner of the robot, which she calls Judo. Nobita reluctantly leads her to the mirror-world mechanism and hands over the psychic controller. Lilulu offers to forgive Nobita for taking the robot if she can use the mirror world, but insists on keeping the arrangement secret.

That night, Nobita probes the mirror world and discovers Lilulu leading a group of robots in the construction of a colossal facility. Doraemon follows Nobita’s trail, and the two learn that the robots are preparing to invade Earth. The android Lilulu leads Zanda Cross in pursuit, but it’s too large to fit through the portal and ends up destroying it, trapping the invasion force in the mirror world. Nobita and Doraemon rejoice, thinking Earth is saved.

The next day, Doraemon translates through the Translation Jelly to reveal that the orb is actually Judo, the neural brain meant to pilot Zanda Cross. Judo confesses that it has already signaled the rest of the robot army to begin their invasion of Earth.

With disbelief from adults, Nobita and friends recruit Suneo [Kaneta Kimotsuki], Gian (Takeshi Goda) [Kazuya Tatekabe], and Micross (who Doraemon has given sentience and the ability to talk) to help stop the threat. They reprogram Judo with Zanda Cross to be an ally, and they use Doraemon’s World Entrance Oil on Shizuka’s bathtub to create another entry point to the mirror world. Shizuka ends up in the mirror world and finds an injured Lilulu, who is revealed to be an android. Lilulu tries to kill Shizuka upon learning she’s human, but is knocked out and tended to by Shizuka, who refuses to believe Lilulu is evil at heart. Lilulu shares the history of her home planet Mechatopia, explaining how robots were created by God after humanity was abandoned. Robots eventually liberated themselves, but decided to invade Earth to enslave humanity as a result of their violent origins. Shizuka notes the parallel with human history, and Lilulu grows angry, attacking her before collapsing from her injuries.

Meanwhile, Nobita and friends lay out a plan to lure the invaders into the mirror world using a lake as the entrance. The robot army lands, sweeping through major cities, but finds no sign of living people. Lilulu escapes and meets with the army’s leader, but she keeps the truth about the mirror world hidden and pleads for peace, arguing that humans and robots are not so different after all. Enraged, the robot commander sentences Lilulu to death, only to have Nobita and Doraemon intervene to rescue her.

The robots uncover the ruse when they realize the planet is reversed in the mirror world. They regroup at the lake entrance, aiming to return to the real world, but Nobita and friends are already waiting. Meanwhile, Shizuka, Lilulu, and Micross stay behind to use Doraemon’s time machine to travel back to ancient Mechatopia and plead with God to rewrite their history. They meet the frail deity, who agrees to reprogram the two progenitor robots, Amu and Imu, but cannot finish the work himself; Lilulu volunteers to complete the reprogramming, fully aware that doing so will erase her own existence.

Back in the present, the invasion teeters on defeat as the robots begin to vanish. In Mechatopia of the past, Lilulu disappears after a final, poignant handshake with Shizuka. The present-day team mourns Lilulu while acknowledging her sacrifice.

Some time later, Nobita, after school, looks out and spots Lilulu flying outside the window. He bursts out to tell his friends, declaring that Lilulu has become an angel, though they remain doubtful. As the end credits roll, Lilulu soars through space, waving goodbye to Earth.