For reasons that defy logic, the excellent This Island Earth was held up for ridicule as an allegedly bad movie in the film version of TV's Mystery Science Theater. If not the best science-fiction film of the 1950s, Earth is certainly one of the most intelligent and elaborate. The story begins when the image of Exeter (Jeff Morrow), a huge-domed scientific genius from the planet Metaluna, appears on an experimental 3D television screen. Exeter invites several noted scientists from around the world to work on a top-secret project at Exeter's earthly mansion. Among those accepting the invitation are Cal Meacham (Rex Reason) and his ex-fiancee Ruth Adams (Faith Domergue). Soon, Cal and Ruth learn Exeter's true motives; to use the Earth's atomic knowhow in building a defense shield to protect Metaluna against the enemy planet Zahgon. Eventually, Exeter boards his high-tech flying saucer and whisks Cal and Ruth off to his dying planet, where, among other perils, they are menaced by a hideous mutant. Based on a novel by Raymond F. Jones, This Island Earth is one of those rare 1950s speculative films that holds up as well today as it did when first released, despite the comparative quaintness of the special effects and high-tech paraphernalia. Incidentally, the climactic Metalunan scenes were directed by Universal's resident sci-fi specialist, Jack Arnold.
~ Hal Erickson, All Movie Guide