When computer specialist Paul Bradford proposes to his girl friend, Gwen, she worries that he is too obsessed with his computer, “Cal,” to be a good husband. That night, Paul dreams that he cannot reach Gwen, and, upon waking, is zapped to an alternate universe, where she is chained up under the command of the dark lord “Mestema.” Mestema presents Paul with seven challenges and warns that if he loses, he will claim the souls of him and his fiancée. Strapping a “machine” to Paul’s arm, he instructs him to use it at will, then christens him with the phrase, “Excalibrate!” Later, Paul awakens in a desert, where a stone giant comes to life and attacks him. Using the computer on his arm, Paul programs it to shoot lasers at the creature. After it is destroyed, Paul is transported back to Mestema, and finds that Gwen has gone missing. Paul agrees to play along to save his lover, this guy awakening in a cave surrounded by attacking skeletal zombies. A creature named Ratspit greets him, and explains that he must face his own death. Paul successfully faces his fears, and is once again returned to Mestema’s domain. After, Paul is transported to a “heavy metal” concert, where a band called “W.A.S.P.” performs. The singer zaps Paul unconscious and tortures Gwen, who is tied up. Using his arm computer, Paul destroys the band, and reappears before Mestema. In a flash, Paul finds himself in an ice cave containing the frozen bodies of several creatures and Gwen, who also begins to freeze. As Paul searches for a way to rescue her, Mestema turns up the heat to melt the creatures, which begin attacking Gwen and Paul. Fighting them off, Paul is faced with his next challenge: temptation. When several seductive women surround him, Paul instantly denies their advances. Next, Paul awakens in an attic and sees a newspaper story about a serial killer called the “Slasher,” containing a photograph his latest victim: Gwen. Mestema tells Paul it is the next day’s headline, and he has only one hour to save Gwen's life. Out in the city, Paul is arrested, but sees Gwen on the street from the back of the police car. After he escapes from his handcuffs, Paul leaps from the car and chases after Gwen. As Paul’s computer tells him the whereabouts of the next murder, he races to stop it. Arriving just in time, Paul shoots the Slasher with a laser, and he and Gwen are beamed back to Mestema’s lair. Paul is immediately sent to a cave, where he hears Gwen’s cries for help. Inside, a beast stands in his way and throws explosives at him. Suddenly, the beast transforms into an angel, who tells Paul that he could have won the challenge if he had simply left the cave. When Paul asks if there is anything he can do, the angel says he has already done it. Once again at Mestema’s side, the dark lord taunts Paul. For the final challenge, Paul finds himself in a desert with Gwen, surrounded by abandoned aircrafts. Soon, they are attacked by members of a desert military, who remove the computer from Paul’s arm. Using voice command, Paul blasts the men and flees in a desert vehicle as Gwen shoots their attackers. Mestema causes Paul’s vehicle to lock up and crash head-on into another vehicle. After the fiery explosion, Paul awakens in the lair, and Mestema announces that the game has ended. Paul insults the dark lord, challenging him to a one-on-one fight for his freedom. Free of tricks, magic, and Paul's wrist computer, they battle until Paul chokes Mestema at the edge of a cliff, pushing the dark lord to his death. When Paul loses his balance, the computer shoots a laser beam rope for him to grab, and the couple is transported back home, where Gwen agrees to marry Paul.