5. Saw III (2006)
LionsgateJames Wan and Leigh Whannell's horror juggernaut Saw is one of the most bafflingly popular franchises of all time. Its low-budget, simplistic origins are virtually indistinguishable from the glossy, blood-splattered mess that the series became once Wan and Whannell left it in the hands of others. Saw III was a real turning point for the series, marking the moment when the inherent silliness of the traps - similar to the death sequences in the Final Destination films - became more significant than the scares. The torture Angus Macfadyen's central character goes through is utterly ridiculous and the plotline around Jigsaw's medical condition is laughable. Any film that features DIY brain surgery is probably too silly to properly function. Saw IV may have been the first to have a truly stupid chronological twist, but Saw III was definitely the beginning of the end in terms of logic.