The Invisible Enemy, directed by Byron Haskin.
The first mission to Mars does not go well. Successful landing, some walking around, then horrid screams and radio silence.
Three years later, the second mission has a larger crew, supposedly better disciplined and definitely over-managed. They don't know what they're facing but have brought nuclear bazookas just in case.
Despite all that their survival skills seem about nil. After more deaths they discover the awful truth: Martian Sand Sharks.
I loved these rocketship adventures as a kid, but this episode has little Outer Limits in it. They would need to play up the mystery, the boundaries of the knowable and how that reflects in the human soul. But they don't.
They do introduce a thriller countdown timer, now a cliche, but when did that start?
Familiar faces:
Adam West -- Robinson Crusoe on Mars (1964), the TV Batman.
Joe Maross -- Run Silent Run Deep (1958), Elmer Gantry (1960), Sometimes a Great Notion (1970).
Robert DoQui -- Coffy (1973), three Robocop films -- in his debut.
Rudy Solari -- Star Trek The Paradise Syndrome.
Ted Knight.
Byron Haskin was a natural director for a Martian adventure, having done The War of the Worlds (1953) and Robinson Crusoe on Mars (1964). He said the script was a disaster and he rewrote it in the days just before filming.
Bad science is traditional in SF movies and I try not to gripe. Just noting:
Their Mars has a breathable atmosphere.
The first mission had speed of light radio, but the second has the new instantaneous laser communication with Earth.
The planet is lifeless apart from one flower (snip!) so what do the sand sharks live on?
From whence comes their hunger for blood? How often do wandering astronauts come by?
The Blu-ray commentary track is by Craig Beam.