9. Slither (2006)
Slither is a singular sort of film. Despite being a box office failure, it was a hit with critics, and has since achieved cult status. It also was written and directed by a young(er) James Gunn, and starred Elizabeth Banks, Nathan Fillion, Michael Rooker, and Jenna Fischer. Though the disappointing box office explains why no sequel was immediately forthcoming, Gunn’s rise to fame (as well as a number of Slither‘s actors’) could have made it possible further down the line. Alas, Slither 2 never arrived.
That’s strange, because Slither actually directly teased a sequel in a post-credits scene (even before the idea was popularized by the MCU). After defeating the extraterrestrial parasite and the people it infected, Slither‘s heroes leave the scene of the carnage to seek help. However, a post-credits shows a cat approaching the infected corpse of Grant, and the alien moving on to a new feline host.
As Slither subtly lampooned action-horror movies, it’s not entirely unsurprising that Gunn never opted to pay off the sequel tease. As it stands, it comes off as a dig at the perpetual sequels of horror franchises, with there always being some way that the villain survives to fight again. Even so, a follow-up to Slither would have been excellent, and it’s a shame that one hasn’t been made.