The Green Slime (1968)

When an asteroid is headed on a collusion course with Earth, a team of astronauts is sent on a mission to detonate explosions on the asteroid which would break it up before it has a chance to reach Earth. However, a piece of green slime from the asteroid attaches itself to one of the astronauts and when they return to the space station, the slime multiplies into living murderous creatures. Made in Japan and directed by Kinji Fukasaku (who co-directed the Japanese sequences in TORA TORA TORA) with American actors but Japanese personnel behind the camera, this is a marvelously cheesy creature feature with tacky special effects and miniatures that are almost adorable in their cheesiness. The "green slime" creatures look like avocados with tentacles and there's a hilarious title song (sample lyrics: "Is it something in your head, will you believe it when you're dead, green slime, green slime, green slime"). The square jawed hero is Robert Horton, luscious Luciana Paluzzi is the space station doctor and Richard Jaeckel is the incompetent commander of the space station.