An affectionate homage to gooey, off-kilter horror movies (see: all things Troma, David Cronenberg's Shivers, Fred Dekker, The Blob, and so much more), this movie has one unexpected thing: A heart. I guess you could say that SLiTHER is to comedic horror what The 40 Year Old Virgin is to sex comedies.

While I must confess I have not seen Tromeo and Juliet, nor any of writer/director James Gunn's earliest work, I have been a fan since 2002 when the silly but subversive Scooby Doo movie came out, and my admiration grew with the advent of his inspired adaptation of Dawn of the Dead in 2004. With his directorial debut of SLiTHER, Gunn's goofy sense of humor goes into gooey overdrive and hits all the right notes (even if the signature song from 80s has-beens Air Supply doesn't).

SLiTHER combines elements of small town zaniness, Martian invasion, married romance, and homicidal zombies in a melting pot of a movie starring Michael Rooker (brilliant) and Elizabeth Banks (adorable). The pair play a longtime husband and wife whose love life may be cold, but their larva life is just heating up: When Grant's brain is invaded by maggot-like aliens, it's up to Starla to save him and the world!

The whole mess begins and ends in the sleepy suburb of Wheelsy, NC. It's a small town with even smaller aspirations, but it does boast its very own police station. The cop shop is headed up by Police Chief Bill Pardy (Nathan Fillion), a man with a lot on his worried mind. His deputy gives Barney Fife a bad name; his dispatcher is a ditz; his former flame Starla has married another man; and, yeah, squid-like aliens have crash landed in Wheelsy and are trying to take over.

The aliens' first victim is Grant, who spreads the venomous virus to his neighbor Brenda (Brenda James), who in turn gives sickening birth to a litter of thousands of slimy, slithery embryos who slink out and look for human hosts to zombify. As the town turns, so too does their "father" metamorphosizing into a Lovecraftian squid creature who listens to Air Supply and eats puppies for breakfast, Grant is a foul force to be reckoned with.

There are some tremendously amusing performances from the supporting cast, especially Gregg Henry as the caustic, sarcastic Mr. Pibb addicted town mayor, but the real star here is Gunn: SLiTHER is his baby and it shows.

A groovy gross-out with snorts, scares and sentiment, SLiTHER is thus far the must-see frightfully funny movie of the year.