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Leprechaun 4: In Space, is the fourth movie in the Leprechaun series.
On a remote planet, the Leprechaun attempts to court a princess named Zarina, in a plot to become king of her home planet. A group of space marines on a search and destroy mission attack and kill the Leprechaun and one of the marines, Kowalski, urinates on the Leprechaun's body. The marines return to their ship with Zarina, where their leader, the half-robotic Dr. Mittenhand, explains his plans to use Zarina's regenerative DNA to recreate his own mutilated body. Elsewhere on the ship, the Leprechaun violently emerges from Kowalski's penis. The Leprechaun then kills most of the crew members in various gruesome and absurd ways.
While pursuing Zarina, the Leprechaun injects Mittenhand with a mixture of Zarina's DNA and the remains of a blended scorpion and tarantula, before initiating the ship's self-destruct mechanism. A surviving marine, Sticks, rushes to the bridge to defuse the self-destruct but is stopped by a password prompt. The other survivors confront the Leprechaun in the cargo bay, who has grown to many times his own size after being exposed to Dr. Mittenhand's experimental enlargement ray.
Sticks is tangled in webs by Mittenhand, who has mutated into a spider-like creature and assumed the name "Mittenspider." The other survivors, the marine Books and the ship's doctor Tina Reeves, rescue Sticks and spray Mittenspider with liquid nitrogen and shoot him, shattering his body. Books opens the airlock so the giant Leprechaun is sucked into space and explodes. Books joins the others at the helm and they deduce that the password is "Wizard," since Dr. Mittenhand previously referred to himself as "the wizard behind the curtain," stopping the self-destruct with only seconds to spare. The survivors rejoice and Books and Tina kiss as the spaceship flies past the remains of the giant Leprechaun's body. They fly past his fist, clenched with middle finger extended.