Omulan!

The first manned expedition to Mars is invaded by an unknown life form, which stows away on the rescue ship.

A space-obsessed man gets the opportunity of a lifetime thanks to a Mars colonization program but finds his plans compromised by his feelings for a woman who brings him down to Earth.

A spaceship is sent to Mars after an alien distress signal is picked up. They find one survivor, but when a crew member is found drained of blood it's evident they have rescued a bloodsucking monster. Uses footage from Encounter in Space (1963).

While scavenging the deep ends of a derelict space station, a group of young space colonizers come face to face with the most terrifying life form in the universe.

The first manned spacecraft, fired from an English launchpad, is lost from radar before roaring back to Earth and crashing in a farmer's field. The rocket is found to contain only one of the three men who took off in it; and he is unable to talk but appears to be undergoing a torturous physical and mental metamorphosis.

After landing on a mysterious planet, a team of astronauts begin to turn on each other, swayed by the uncertain influence of the planet and its strange inhabitants.

When the first manned flight to Venus returns to Earth, the rocket crash-lands in the Mediterranean near a small Italian fishing village. The locals manage to save one of the astronauts Colonel Calder, the mission commander. A young boy also recovers what turns out to be a specimen of an alien creature. Growing at a fantastic rate, it manages to escape and eventually threatens the city of Rome.