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.
Peter Graves, Greg Morris and Lynda Day George all reprised their roles from the original series.
The device with which Jim Phelps gets his instructions is tightly secured. To get access he has to scan his thumb first and then he has to type in a security code, which is always 3 digits long, except in "The Condemned" where it is just '59' and "For Art's Sake" where it is '.34598', to get the data disc he then has to press the red button.
The keypad in general contains a the numbers 0 to 9, . and =. Below are 4 buttons: red, black, white and grey.
While red is to confirm the security code and get the disk, the white one is for scrolling the recording back, as shown in "Reprisal" (the only time ever that this is shown).
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.
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.