9 Horror Movie Heroes Killed By Their Own Vices

In Deep Blue Sea, Saffron Burrows' Dr. Susan McCallister has good intentions but questionable methods.

At the heart of Renny Harlin's 1999 movie, we have a group of scientists doing research on mako sharks in the hope of combating Alzheimer's disease and reactivating brain cells.

While this is all clearly very noble, the caveat here is the early reveal that McCallister and colleague Dr. Jim Whitlock (Stellan Skarsgård) had genetically altered these sharks in order to increase their brain size - which results in super smart, super angry sharks intent of taking down the research facility and all in it.

It's this research work that literally comes back to bite Doc McAllister - and Whitlock - on the backside by the time Deep Blue Sea rolls to a close.

Not only did Susan's obsession with finding an Alzheimer's cure by any means necessary result in her being trapped by a pack of ferocious mako sharks, she ended up having her research destroyed, before she then ends up devoured by one of her own modified sharks mere minutes before Deep Blue Sea concludes.