Having crashed in the desert, a dazed June Robbins staggers into a medieval world within a mirage. The Challengers follow to rescue her before the mirage disappears. Captured by knights, the Challengers issue a challenge - a duel with chariots. Despite Sir Rodfold's treachery, the Challengers win, snatch June, and dive out of the city just before it vanishes forever.; Pursuing a criminal, the Challengers find he's partnered with a metallic fugitive from another world. Halanka, the metal alien, pulls their Jeep with magnetism and melts it with heat. Two Challengers rescue an interplanetary lawman, Thark, who comes to their aid. Using Thark's force-field gun, the Challengers get close enough to "bowl" Halanka over.