The aliens get picked up by a rescue ship from Remulak and are brought back to the planet, along with Seedling and Turnbull, who were trying to arrest them. Beldar meets with the Highmaster and gives him Seedling and Turnbull as gifts, but the Highmaster then notices that Beldar had his teeth capped, and this alteration of his “face portal” constitutes treason, so he sentences Beldar to fight the Garthok, a huge vicious beast. Beldar manages to kill it by combining his weapons into a golf club and hitting a rock down its throat to choke it. For his victory, the Highmaster grants him a request, and Beldar requests that he and his family be allowed to return to Earth so that they may conquer it and enslave humanity. He also gets permission to have Seedling join them because of how he is of a higher office than Turnbull, and Turnbull makes the best of his new situation by becoming the Highmaster’s flunky.
Beldar returns to Earth with a fleet of Remulakian ships, but after he enters the planet first, he thinking about how important it is for Connie to look up to him tricks the fleet into thinking that there are powerful laser guns in Earth’s satellites and orders them to retreat, then gets himself, his family, and Seedling out of the ship and stages its destruction so the fleet will think that the lasers have killed them. The fleet goes back to Remulak, and Seedling agrees to give Beldar a green card in exchange for being allowed to live. The aliens settle into a permanent life on Earth, and Connie’s human boyfriend Ronnie takes her to their high school prom.
One day, Beldar (Dan Aykroyd) and Prymaat (Jane Curtin) get a call from Remulak while they are speaking with Seedling (Michael McKean) and Turnbull (David Spade), who are disguised as Jehovah’s Witnesses to gather information on them. After forcing Seedling and Turnbull out of the house, they answer the call and find out that their long-awaited rescue ship will be coming to collect them and Connie (Michelle Burke) tonight. At the country club costume party that same night, Beldar gives Connie the news, which saddens her because it means that she will have to end her relationship with Ronnie (Chris Farley). She takes Ronnie away from the party back to her family’s house to break the news that she is an alien and will be leaving that night, but he tells her he loves her, and they end up having the Remulakian version of sex with her parents’ senso rings until Beldar and Prymaat return home and catch them in the act. Connie tells them that she wants to stay with Ronnie, and when Beldar shoots that down, Ronnie offers to come to Remulak with her.
Suddenly, Seedling, Turnbull, and the rest of the INS appear outside to arrest them. Despite Ronnie trying to provide a diversion to give the aliens a chance to escape, the aliens get cornered in their car. As Seedling approaches them, the Remulakian ship appears and attaches a magnet to the car and pulls them up, and Connie and Ronnie proclaim their love for each other. Refusing to let them get away, Seedling grabs hold of the bumper, and Turnbull then grabs hold of Seedling. They are brought aboard and encased in glass tubes, with Beldar intending to have them be given as gifts to the Highmaster (Dave Thomas).
On Remulak, Beldar meets with the Highmaster and gives him his gifts from Earth, but the Highmaster soon notices that he had his teeth capped during his time on Earth. Since this alteration of his “face portal” constitutes treason on Remulak, the Highmaster declares that he will have to fight the Garthok, a huge vicious beast, as punishment. Beldar manages to kill the Garthok by combining his weapons into a golf club and hitting a rock into the beast’s throat, choking it to death. The Highmaster grants Beldar a request for his victory, and he requests that he and his family be permitted to return to Earth so that he may conquer the planet and enslave humanity, and he wishes to take both Seedling and Turnbull with him. The Highmaster refuses to allow both of them to go, so Beldar chooses Seedling because of how he is of a higher rank. Turnbull makes the best of his new situation by becoming the Highmaster’s flunky.
Beldar, Prymaat, and Connie lead a fleet of Remulakian ships back to Earth, and the family lands on Earth first with Beldar instructing the fleet to wait in the outer atmosphere until he gives the order to strike. After taking a look at Connie, Beldar understands that Connie’s happiness and positive perception of him mean more than planetary conquest, so he proceeds to fake a warning of having detected powerful laser guns in Earth’s satellites and orders the fleet to retreat. He then activates his ship’s self-destruct sequence, takes a remote control to launch the ship without him at the helm, and then vacates it with his family and Seedling. He steers the ship skyward and it explodes, and the Remulakians believe that he and his family have perished and thus opt to forget about invading Earth and return to their homeworld. Beldar makes a deal with Seedling where he will let him live in exchange for a green card, and Seedling accepts provided that he possess a special job skill that no other U.S. citizen has, which Beldar informs him will pose no problem.
Some time later, the aliens have settled into their permanent life on Earth, and Ronnie takes Connie to their high school prom.
Thanks Tornado Dragon!