One-Eyed Monster (2008)

So the plot of this movie is that a male porn star's (notoriously large) penis gets taken over by an alien force.  It then attempts to penetrate every orifice it can find, impregnating the target where possible and killing them where it is not.

You're probably thinking to yourself 'that sounds stupid', and trust me, it is.  But it's also surprisingly good fun.

Part of that is because the cast is a cut above the average for low-budget horror, but a bigger credit has to be given to the script.  It has a stupid premise, and it knows it has a stupid premise ... but it never lets that be an excuse to be lazy.  Characters' actions make sense in the context of the admittedly absurd situation in which they find themselves, and their efforts to stop the monster are logical, albeit contrived.

Stick a different monster in as the threat, and tweak a few bits and pieces around the edges, and you'd have a solid if unremarkable direct-to-dvd horror film.  So why the goofy premise?  Well probably to make it get noticed, to be honest.  'Killer Penis!' is good link-bait for today's online horror movie sites, and in today's post-Sharknado world, the marketing benefits of a truly gonzo premise seem pretty obvious.

So sure, this is a silly and immature film, but so was 300.  At least this one was entertaining.