Only two things stayed unchanged in the opening: the striking of the match and the actual display of the title. The rest of the opening title showed clips which varied from episode to episode.
Episode titles were not shown on-screen. Although this became commonplace with dramatic series in the late 1980s, it was unusual in the 1960s for a one-hour action series to not have episode titles.
Many episodes end with a freeze-framed pan-and-tilt shot of the IMF team's getaway vehicle, with series creator Bruce Geller's credit superimposed over the shot.
During the first season, Martin Landau was credited as a special guest star. This was because Landau refused to sign a standard five-year contract, but producer Bruce Geller wanted him badly enough that he agreed to use him on a "guest star" basis. Although Landau ended up appearing in a majority of the Season One episodes, he didn't sign a contract (and then only for a year at a time) until the second season.