First Man Into Space (1959).

The Scoop:
The pilot of the first manned space flight (played by Marshall Thompson) returns to Earth covered with an odd dust that causes him to go on a killing rampage. This somewhat interesting, though overly slow, cheapie from director Robert Day is one of the better of the late-'50s wave of films warning about the perils of the imminent age of manned space travel. Granted, given the quality of the other films of that ilk, that's not saying much. Still, it's an interesting look into the fears of the period, and worth a look for viewers with a soft spot for the genre. The plot was later liberally borrowed for "The Incredible Melting Man" (1975).

Best Bit:
The newspaper headline that refers to the title character as "The Highest Man in the World."

Side Note:
Although the film takes place on an American military base, it was shot in Great Britain. Usually this wouldn't be noticable on-screen, except that many of the base signs use British spellings.

Companion Viewing:
The even-worse "Night of the Blood Beast" (1958) and "Monster a Go-Go" (1965).

Links:
IMDb.

Take a Look:
The trailer: