Capricorn One (1978)
I can't believe no one has recommended this one. The gov't fakes a landing on Mars, then decides that they can't afford to keep the "astronauts" alive! It stars the usual staples of '70's actors, including, wait for it... O.J. Simpson! What's not to riff?
This was actually a satire on those who believed the gov't had somehow faked the Moon landing, but here it was done with Mars.
So bleakly terrible, it actually causes ripples in the space/time continuum when played!