Since 1979, CinemaScore has polled opening-weekend moviegoers, who grade the films they watch on a scale from A+ to F. In 40 years, only 21 movies have received an F.

I watched them all.

Once I regained consciousness and stopped the mysterious nose bleed I got midway through I Know Who Killed Me, I made this list ranking them from the most awful movies I’ve ever seen to some outstanding films that CinemaScore voters got completely wrong. That’s right; while the majority of these titles are bad, a fair number are better than Fs. (More like C-/D+.) A few are legitimately good to great, a nice reminder that while CinemaScore has been an industry standard for decades (as a kid, I used to look up CinemaScores every week in Entertainment Weekly’s box-office chart) it’s only as good as the taste of the people who show up to a movie on its opening weekend.

With the benefit of hindsight, these movies often look very different. Not the first couple movies on this list, though. In those cases, an F might have been too generous...

Gallery — Infamous Box Office Bombs That Are Secretly Good:

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