Little Green Men

Quark is given a shuttle by his cousin and sets off with Rom and Nog to take Nog to Starfleet Academy, secretly carrying a cargo of volatile kemocite to sell along the way. When the ship becomes stuck at warp, possibly through sabotage, Rom's desperate fix of venting the engine exhaust through the kemocite hurls them back to July 1947, and they crash near Roswell, New Mexico. The US military takes the Ferengi for invaders from Mars. Quark sees a chance to sell future technology and build a Ferengi empire on Earth, until Odo, who stowed away on the shuttle, warns that history must not be changed. With help from a sympathetic nurse and a professor, they escape, and Rom uses the last of the kemocite and the energy of an atomic bomb test to send them home. Nog reaches the Academy, Quark has to sell the wrecked shuttle for salvage, and Odo arrests him for smuggling.