There must be 100 or more names listed, some quite famous or at least well known. Granted, these actors only appeared in one scene or on one show, but it seems like everyone in Hollywood stopped by to do a bit in The Lieutanant.
shareA lot of future Star Trek player were in it!
shareThe large guest casts are very common for this era for TV shows of the late 1950s and 1960s (Perry Mason, Wagon Train, Burkes Law, etc.).
It was also fueled by a change in the "status" of television. In the 1940s and a good part of the 1950s tbere was a war/rivalry between the Hollywood movie studios and the young upstart "television".
Movie stars and the bigger names avoided television like the plague. Over time, the rivalry disappeared and the 2 mediums realized there was plenty of business for everyone, and they could actually complement one another.
Thats when all the movie star names flooded over to "TV Land" and made this great wave of guest appearances.