10 Movies You Can Never Finish

6. The Human Centipede 2 (Full Sequence)

The original Human Centipede was ultimately a surprisingly restrained, even tame, horror film, taking its undeniably salacious premise - a mad doctor sewing people together butt-to-mouth - and delivering an oddly pared-down, familiar thriller.

The film became a viral hit and even caught on semi-successfully with the mainstream on home video, but when the sequel was released in 2011, nobody quite expected such a major uptick in objectionable content.

While the original towed the tonal line surprisingly tastefully, the sequel had no such desire, with writer-director Tom Six indulging in excessive sexual violence, splashing all manner of bodily fluids over the screen, and even featuring the mutilation of a newborn baby.

Full Sequence received extensive cuts around the globe, but even then, it's still a stomach-churning sit which only the most hardened purveyors of cinematic torture porn would even entertain suffering through.

Ironically the third film, Final Sequence, verged into full-on parody and so was decidedly easier to watch.

Full Sequence, however, is the only entry into the series that truly gets under the skin, with its aggressively morbid tone and relentlessly miserable depictions of violence.