12 Movies So Good You Overlook Major Flaws

3. The Performances Are Terrible - Saw

Saw is the only movie on this list that didn't exactly review well with critics, but ever since release it has been warmly embraced by genre fans for its unique premise, clever use of its low-budget and, of course, its mind-blowing twist ending.

But there's no getting around it: the acting in this movie sucks.

If this was the first movie you saw acting vet Cary Elwes in, you'd probably assume he was a regular on the straight-to-video circuit, because his hammy line readings and constantly wavering American accent are intensely distracting.

This culminates in an unintentionally hilarious finale where, after cutting off his foot off, Elwes' Dr. Gordon blatantly switches to a British accent and sounds like a coked-up Ozzy Osbourne as he screams, "I'll f***ing kill you!"

As the movie's writer and co-star, Leigh Whannell sadly isn't any better. It's one of his first acting roles and it really shows, bouncing between stiff-as-a-board and wildly over-affected.

Given that about 80% of the movie is just the two of them chained up in a mouldy bathroom exchanging terrible deliveries, it's truly impressive that Saw is as good as it is and has enjoyed so much success.