When film critics insult B-movies, the written jabs often feel unfairly mean-spirited. By definition, motion pictures classified as B-quality were made with less resources than major studio blockbusters and prestigious, A-list-heavy dramas. How can you blame them if they suffer from shitty special effects or have acting so awful that it makes Keanu Reeves look like Marlon Brando?

Then again, so many of these low-budget works are comparable to Illegal Aliens,independent writer-director David Giancola's 2007 babes-versus-E.T.s misfire starring Anna Nicole Smith. In the new documentary Addicted to Fame, also directed by Giancola (who now runs a car rental agency), he puts the wholly inept production of Illegal Aliens front and center, showing how a not-so-talented filmmaker churned sci-fi stool out of little money and inept performers.

By and large, Giancola's Illegal Aliens is only memorable for the fact it was Smith's final acting role before her untimely death. All of the flicks included in the following list of The 25 Worst B-Movies from Outer Space, on the other hand, quickly implant themselves into viewers' brains, for all the wrong reasons. Or, if you're the type of person who'd choose a splendidly bad Ed Wood film over a splendid Natalie Wood performance, it's probably the right reasons.

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Review by Matt Barone (@MBarone)