UFO: the Shirtless SHADO Warriors

Before books like Whitley Strieber's Communion (1985) and Budd Hopkins' Missing Time (1988) popularized the idea of aliens grabbing people from their beds to perform scientific experiments on, the  tv series UFO (1970-71), part of the 1970s British invasion (The Prisoner, The Tomorrow People, The Hitchhiker's Guide to the Galaxy), had a similar premise: in the near future, the worlds' governments become aware that aliens are abducting people to harvest their organs.  They set up the secret organization SHADO to combat them from a fake movie studio, a submarine, and a base on the Moon.

Oddly, everyone at SHADO headquarters, men and women both, wear see-through shirts, so there was a huge amount of beefcake for a science-fiction series.

At first the protagonist was former American astronaut Edward Straker (Ed Bishop).

In the second episode, lone wolf British test pilot Paul Foster (Michael Billington) witnesses a SHADO operation, and is given the choice of signing up or being killed.  Foster decided to join, and Michael Billington soon became the standout star, and a favorite of teen magazines.

In the third episode, Foster is brainwashed by the aliens into attempting to kill Straker.  Later Foster is captured by the aliens, and Straker has to come to the rescue.  The grudging love-hate relationship continued  through the series, and provided fodder for many slash fiction stories.

Only 26 episodes were aired, but there were two novels, comics, toys, action figures, a board game, and eventually a video game. And from 1975 to 1977, the same universe was used for Space: 1999, in which the Moonbase (and the moon with it) is swept away from the Earth's orbit for interstellar adventure.

Later Michael Billington played two-fisted heroes on many British tv series (The Onedin Line, Spearhead, The Collectors) and attended innumerable fan conventions.  He never married. He died in 2005, five days before his UFO costar Ed Bishop.