Without Warning (also known as It Came Without Warning) is a 1980 American horror science fiction film directed by Greydon Clark and starring Jack Palance, Martin Landau, Tarah Nutter, and Kevin Peter Hall. Special effects designer Greg Cannom created the aliens for the low-budget film. The film released on September 26, 1980 and was released on home video for the first time on August 5, 2014 through Shout! Factory's Scream Factory label in a Blu-ray/DVD combo pack.

The film is credited with being an inspiration for the 1987 film Predator, both of which star Kevin Peter Hall as a costumed hunter of alien origin.Dan Grodnik optioned the script in 1978 and hired Bennett Tramer to do a rewrite. Half way through the script, Tramer went to Grodnik and told him he had an epiphany, that he couldn't finish the sci-fi script as he just realized he was a comedy writer. He handed Grodnik the unfinished script with apologies. Grodnik sat down in his living room on an IBM typewriter on top of a TV tray table and finished the script. Shortly thereafter the film went into production. When it was time to list the credits on screen Grodnik asked Tramer if he wanted his credit to read, Bennett Tramer or Ben Tramer. Because Tramer was trying to break into the comedy writing business he felt putting his name on the film wasn't a good idea so he asked to be credited as Ben Nett. Grodnik explained to Tramer, who had no credits at the time, that even the great director Robert Wise, who directed The Sound of Music and West Side Story started off with a horror film entitled The Curse of the Cat People, and that didn't hurt his career but Tramer was adamant that the film credit him as Ben Nett. Tramer went on to write the TV series Saved by the Bell.