Semi-classic science fiction film from 1955. It was directed by Jack Arnold and written by Robert M. Fresco and Martin Berkeley, based on a story by Fresco and Arnold. It starred John Agar as Dr. Matt Hastings, Mara Corday as Stephanie "Steve" Clayton, and Leo G. Carroll as Professor Gerald Deemer. Clint Eastwood has a short cameo at the end of the movie.
Basic plot: Professor Deemer is working on an experimental growth hormone in the Arizona desert. It works great on animals, but it causes acromegaly in humans. Deformed and deranged, Deemer's assistant trashes the laboratory, releasing a tarantula that soon grows into an immense horror that menaces everyone within crawling distance!
Okay, in a lot of ways, this is a cheesy, cheesy movie. As an actor, John Agar makes a great square-jawed concrete block, and Leo G. Carroll was in much better movies than this. "Tarantula" also includes my favorite piece of retro-sexist dialogue ever: "Well, whattya know! Give women the vote, and what do you get? Lady scientists!" Wow, if that don't say "1950s" to you, I don't know what will.
However, I dearly love this movie, both because of and in spite of the cheese. Next to "Them!", this is the best of the Giant Bug movies of the '50s. The mood is eerie throughout the film, and the vast, empty desert is capably used to heighten the tension of the movie. The special effects, though relatively simple, are quite realistic, even unsettling -- for one thing, a real spider was used, instead of the fake ants in "Them!", and they even manage to give it a convincing shadow.