To this day, Lee Majors is known to most Americans as Steve Austin, aka “The Six Million Dollar Man,” though the signature science-fiction program ended 40 years ago.

“The Six Million Dollar Man” was a huge step forward for grounded science-fiction on television, and it remains supremely popular today. There are even still reports that Mark Wahlberg is working on a reboot film based on the show, to be titled “The Six Billion Dollar Man” — obviously with an upgraded dollar amount because, well, inflation just plain stinks.

Here’s a look at five facts you probably never knew about the series that transformed Lee Majors into Steve Austin, as 2018 marks 40 years since the show said its goodbyes.

1.) Majors did a lot of stunts of his own. During the action scenes, viewers often saw the full body and face of Majors, something that usually takes camera and editing work due to the presence in most cases of stuntmen.

Although he couldn’t do every stunt, Majors had the motivation and athleticism to do what he believes is more than 80% of his own stunts (he played college football).

2.) Majors was almost substituted. In the midst of contract conflicts in 1977, creators allegedly started to sniff around to fill the shoes of their lead actors for fresh applicants.

Interestingly enough, Jenner would end up being a substitute for an actor on another famous show, “CHiPs.” The move was highly controversial with fans and lasted only a handful of episodes. With Majors, good thing manufacturers worked out stuff.

3.) On the display, Farrah Fawcett did not have one role— but four. Farrah Fawcett, the superstar of “Charlie’s Angels,” was married to Lee Majors while both were on famous TV shows. She appeared on “The Six Million Dollar Man,” however, before Fawcett scored her gig on “Angels,” playing three different characters in four different episodes.

4.) The performance was based on a novel. At the time, “The Six Million Dollar Man” may have seemed like an original concept, but it was loosely based on Martin Caidin’s best-selling novel, “Cyborg,” released in 1972. It inspired several sequels in the form of a book.

5.) There were six films on television. The show was out of its primary television programming a successful film franchise. Lee Majors took on Steve Austin’s role in three made-for-television movies before the series aired its first episode.