Urusei Yatsura: Only You (1983)
When everyone in town receives invitations to Ataru's wedding, they are shocked to see that his sweetheart Lum is not the bride. Eventually they learn that when Ataru was playing games as a little boy, he stepped on a girl's shadow. Unbeknownst to him, the girl was from extraterrestrial culture where stepping on one's shadow is a form of marriage proposal, and now she and her family have come back to see that Ataru keeps his promise. If he manages to get out of this without being killed by her folks, he'll still have to avoid being torn apart by the hands of Lum.
- The film starts with a flashback to two children playing a game of shadow-tag (the object is to step on the shadow of the person who is it). As the little boy does so, the girl then informs him that this is a sign that he must marry her. The little boy agrees to this, and a spaceship descends to retrieve the little girl, who explains she will eventually return for the little boy when they are older.
The film then cuts to the present day, where a strange-looking messenger drops off wedding invitations to everyone who knows Ataru Moroboshi. The letter confuses some, but infuriates a number of people. When Ataru arrives at school with Lum, neither of them know anything about the invitations, and hushed whispers are heard in the halls about the invitation mentioning Ataru and a girl named Elle.
Ataru is tricked into going to the school's clocktower, where he is confronted and tied up by Megane, Perm, Kakugari and Chibi. The four attempt to torture Ataru to reveal who Elle is, but Ataru has no idea. Soon after, Shinobu shows up and is also intent to know who Elle is. Ataru barely escapes from her clutches when Lum shows up, and electro-shocks him. Shutaro Mendo soon after arrives with a battalion to the school's gates, and finds Ataru, intending to slice him to ribbons as well, when a strange spacecraft descends over the school.
From the ship descends a woman who requests Ataru accompany her. Ataru eagerly thinks this girl is Elle, but it turns out she is the ship's captain. She then begins to show Ataru to an old woman next to her, who Ataru quickly runs from. However, the old woman explains she is Elle's nanny, and encapsulates Ataru in a protective invisible bubble to prevent any further damage from befalling him before the wedding day. True to the old woman's words, Lum's electro-shocks can't penetrate the protective covering. Ataru eagerly heads home to prepare to wed Elle, leaving Lum heartbroken, and flying off with her cousin Ten following close behind.
Lum wanders around the town with Ten, when she encounters her friend Benten. As they talk, Benten reveals that Lum was being followed, but their follower quickly creates a diversion and disappears. Lum and Benten go to a noodle stand where Benten explains that almost everyone received an invitation to the wedding, even her. Lum is still not sure what to do, when Benten whispers an idea to her. Lum is at first shocked, but then decides to go along with her friend's idea.
Lum quickly pilots her UFO to the Moroboshi household, where she explains that she is taking Ataru to her planet where they will be married. Ataru refuses to go, but Lum uses a large suction device to vacuum him up, along with Ataru's parents, and Sakurambo (who happened to stop by to freeload off the Moroboshi's again).
Benten takes care of retrieving the other people that Lum and Ataru know, and they take off into space, where they are joined by Oyuki, Ran, and Princess Kurama, before rendezvousing with a fleet from Lum's planet, headed up by her parents.
Some technicians aboard Lum's father's ship manage to (explosively) remove the protective barrier surrounding Ataru, and he and Lum are taken to a chamber to meet his and her parents. Both are in agreement that the two should wed, and Ataru, the pressure upon him, quietly agrees.
Lum then takes Ataru to a private room, where she presents him with an engagement ring. After much persuasion, Ataru puts it on, but not before the moment is broken as Elle's fleet of fighters have come across the Oni warships, and a battle ensues. Ataru then requests that Lum turn him over to Elle, but she refuses to do so, knocking Ataru out. Unknown to her, a spy has been aboard the ship, and knocks her out as well.
The spy takes Ataru, and puts him aboard a ship. Unknown to the spy, it's the same ship that houses the rest of Ataru's friends and cohorts from Earth.
Lum awakes sometime afterward, and takes flight in a broken spacecraft on the ship. However, the ship malfunctions, blowing up, but Lum ejects safely. As she watches, The spy's ship rendezvous with Elle's fleet, and they disappear.
Ataru and his cohorts make it to Planet Elle, where most are rather shaken up over not being able to go back to Earth. Megane is beside himself regarding what to do, but Ataru feels that being on the planet will hold potential for his dreams. Seeing as he'll be wedding Elle, he'll be the ruler of the planet...and can then create an ultimate harem!
The group is escorted to the main palace where they meet the red-haired Elle...who at first mistakes Mendo for Ataru. After wandering around the palace gardens, Elle retires to her room, but not before requesting to Mendo to meet her sometime afterward.
Mendo complies, and is then shown into a special room...where it is revealed that Elle has a shocking hobby. In the cold-storage room are numerous handsome men who have been frozen, and Elle wishes to do the same with Mendo. unknown to the two of them, Ataru and several of the others have been spying on the two.
Elle then attempts to freeze Mendo, but not before Shinobu shows up, destroying the machine. She attempts to escape with Mendo, but soon everyone is captured. Elle pleads with Ataru to be understanding, but he refuses to contemplate marrying her now. Elle then has him and the others locked up, still intent to go ahead with the wedding.
Ataru is locked in the same room as Lum's cousin, Ten. Ten then chastises Ataru for being so stupid, and Ataru the curses himself for being an idiot as well, ignoring Lum who always seemed to be there for him.