Richard Crouse

In The Host, the hotly anticipated new film written by Twilight scribe Stephenie Meyer, a parasitic alien is injected into the body of Melanie Stryder, played by Saoirse Ronan.

Sounds grim, but remember, this is from the lady who gave us sparkly vampires and undying love, so the alien inside is kind of a lovesick creature who helps the host body find her loved ones.

That’s a lot more benign than other parasitic alien movies.

The most famous alien organism — in the movie Alien, naturally — literally burst on the screen, poking its horrible head through the chest of John Hurt in one of cinema’s most indelibly creepy moments.

To get a natural reaction from his actors, director Ridley Scott didn’t fully explain what was about to happen as they shot the scene.

“Everyone (on the crew) was wearing raincoats,” said Sigourney Weaver. “We should have been a little suspicious.”

When the alien came careening out of Hurt’s body the actors were genuinely surprised.

Blood oozed all over the set and the shock was so intense it’s alleged that Veronica Cartwright passed out and Yaphet Kotto was so freaked out he went to his room and wouldn’t talk to anyone.

Much less bloody is The Puppet Masters, which sees the earth invaded by alien “slugs” that piggyback on people’s backs, controlling their minds.

Based on the Robert A. Heinlein 1951 novel, the film starred Donald Sutherland, who also appeared in one of the genre’s classics, Invasion of the Body Snatchers.

The original movie of the story, taken from Jack Finney’s classic novel The Body Snatchers, dates from 1956 and has been declared by the Library of Congress as “culturally, historically, or esthetically significant,” but it is the Sutherland version, from 1978, that is truly chilling.

The story of alien infiltration — humans are being replaced one by one by emotionless ETs — was called “the best film of its kind ever made” by The New Yorker’s Pauline Kael and a movie that “validates the entire concept of remakes,” according to Variety.

The strangest movie parasite wasn’t an alien, but a bug that feeds on fear.

In the Tingler, these parasites attach themselves to their host’s spine and tingle when the host is frightened or scared.

In its original 1959 run it was shown with the Percepto! gimmick that gave some of the theatre seats a small electrical jolt — or tingle — during the movie’s climax.