10 Horror Films Ruined by WTF Endings

The bad far outweighs the good when it comes to shark-centred horror. 

Be that as it may, 47 Meters Down showed promise due to its intriguing premise. While sisters, Lisa and Kate, are cage diving in Mexico, their cage plummets to the ocean floor. When a school of great whites close in, the pair realise they need to escape before they run out of oxygen.

During the climax, Kate leaves the cage to locate an air tank, when she's suddenly chomped on by a shark. Lisa emerges from the cage to save her sister and brings her to the surface. 

To avoid getting the bends, the duo have to wait five minutes to decompress, forcing them to fend off a group of bloodthirsty sharks, even though the surface is only a few meters away. When the two are rescued by a boat, it's a gratifying moment, knowing the hell Lisa and Kate have endured.

But in the next scene, it's revealed Lisa is still trapped in the cage and had hallucinated the entire third act after breathing in too much nitrogen. Worse still, Lisa realises Kate died when she was bittenb by the great white earlier.

Lisa is rescued later but it's incredibly anticlimactic, since it invalidates the hope and tension built up in the supposed final act.