I usually kept all 4 under the same category of "Best French Horror," but if giving a list it'd consist of Inside, Martyrs, Haute Tension, then Frontier(s).
Martyrs wouldve been the best had they kept up the insane fist half instead of splitting it.
Gotta ask why though. You due for a 7-8 hr extreme gore fest? Id skip dinner if its your first time viewing them.
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