Power Rangers in Space is the fourth major incarnation of the long-running Power Rangers live action TV series. Power Rangers was often seen as a rival, and later successor, to Teenage Mutant Ninja Turtles' popularity. The first entry, Mighty Morphin Power Rangers, first aired in 1993, with Power Rangers in Space launching in 1998. The series was a heavily altered version of Japan's even longer-running Super Sentai series; Power Rangers in Space, in particular, was modified from the 21st incarnation of the series, Denji Sentai MegaRanger.
The Power Rangers of this season, commonly referred to as the "Space Rangers", consisted of Andros (Red), Theodore J. Jarvis 'T.J.' Johnson (Blue), Carlos Valerte (Black), Ashley Hammond (Yellow), and Cassie Chan (Pink) (a sixth Ranger, Zhane the Silver Ranger, came later and was not present in the Ninja Turtles: The Next Mutation crossover.)
At the end of the Power Rangers in Space episode Save Our Ship, the villain Astronema approaches New York City and the five Turtles (in their Ninja Turtles: The Next Mutation incarnations) exit a manhole.
The full crossover begins in the following episode, Shell Shocked. The Turtles are placed under a spell by Astronema, and pretend to be friendly to the Rangers to gain their trust and sabotage their ship. Upon the spell being disrupted, the Turtles return to their former selves and ally with the Rangers, defeating Astronema.
Before the Turtles return home, the Rangers allow them to use their space-faring surfboard-like transports, the Galaxy Gliders, to cruise around space with for a short time. despite the Turtles not wearing any special equipment such as space suits, oxygen tanks, and helmets, they are shown to be unaffected by the drawbacks of space on a living being.