The series was originally planned to be a limited series. A new cast was hired to play the characters from the original Mission: Impossible (1966), and the episodes were all going to remake original series scripts. This changed when Peter Graves returned to the role of Jim Phelps; the other characters were then renamed, and the show became a continuation of the original. One of the new cast members was Greg Morris's son, Phil, cast as his dad's character Barney Collier. His character was renamed Grant Collier, and he became Barney's son.
The original Star Trek and the original Mission: Impossible were both filmed at Desilu studios. As a result, many character actors were seen on both shows in memorable ways. There is an interesting continuation of this in the second MI series and in Star Trek: The Next Generation. John de Lancie plays the unpredictable main antagonist in both pilot episodes.
Each time Phelps gets his recorded instructions in the first season, he types in a security code to get access to a compartment containing a data disc. Although the code changes between episodes, it always contains at least one 5.
Due to the writers' strike of 1988-89, the revived series was originally going to consist entirely of updated versions of stories from the original series. When the strike ended, the show began producing new scripts. However, four of the first five episodes of the revival are remakes of original series episodes.
Terry Markwell did not renew her contract for the remainder of the first season of Mission Impossible as she was dissatisfied with the screen time her character Casey Randall was getting in the series. She was replaced by Jane Badler.