Steve and Dan encounter two time-travelling people their size, Throg and Berna, who escape a SID agent by using an amazing device called the STM—(Space-Time Manipulator). Throg demonstrates the abilities of the STM which can send anyone, to anywhere, to any time. Steve believes he could use the device to return to Earth and change everyone's current predicament by avoiding taking off for the fateful flight of the Spindrift. Steve manages to gets a hold of the device and he and Dan teleport back to Los Angeles spaceport on Earth just before the flight. Throg and Berna soon arrive and angrily explain that it is forbidden to change history, but Steve and Dan do not want to go back to the giant world so easily. Oddly, though the Spindrift left on their trip on June 12, 1983 in the pilot, their departure date here is September 25, 1983. The storyline for this episode is lifted from the Lost In Space episode The Time Merchant.