Mission: Impossible: Season 04 (1969)

Fans of Mission: Impossible greeted the start of the series' fourth season with fear and trepidation. To be sure, the series was still second to none in serving up exciting action sequences and labyrinthine counterespionage plotlines. And, yes, most of the familiar cast members were still in attendance, including Peter Graves as IMF leader Jim Phelps, Greg Morris as electronics expert Barney Collier, and Peter Lupus as "house athlete" Willie Armitage. But how, asked the fans, would the series be able to survive the defection of its two most popular regulars, Barbara Bain and Martin Landau? In the case of Landau, the series' producers wasted no time in finding a suitable substitute. Replacing Landau's character of Rollin Hand, a professional actor who skill with disguises and dialects made him indispensable during the IMF's many "infiltration" assignments, the producers came up with professional magician "The Great Paris," who shared Rollin's expertise at makeup and vocal dexterity and could fulfill the same function on the IMF team. Better still, Paris was played by Leonard Nimoy, an actor whose popularity was at its peak by virtue of his recent three-year stint as Mr. Spock on Star Trek. Although Paris could easily have been a Rollin Hand clone with a lesser performer, the brilliant Nimoy came up with a characterization -- and a variety of false identities -- uniquely his own, and would continue doing so until he himself left the series at the end of season five. Unfortunately, the producers were never able to come up with an entirely successful replacement for Barbara Bain; indeed, no fewer than four actresses would be tried out as the "new" Cinnamon (albeit under different character names) for the remainder of the series' run. Although not officially a regular during season four, the talented Lee Meriwether would show up from time to time as "Tracey," a lovely if nondescript Cinnamon substitute. Despite the cast shakeups, Mission: Impossible continued to turn out first-rate episodes during its fourth year on the air, notably the two-part "The Controllers," and the series' only three-parter, "The Falcon," arguably the best-ever showcase for series newcomers Nimoy and Meriwether. Unfortunately, the loss of Landau and Bain proved highly detrimental to the show's ratings: after an all-time-high during season three, the show didn't even crack the Top 30 during season four. ~ Hal Erickson, Rovi