At the beginning and especially at the end, Julianna Margulies spends extensive time in the ocean, wearing nothing but cargo pants and a T-shirt. Considering the movie takes place just off the Bering Strait, wouldn't she have quickly frozen to death?
The studio and producer Joel Silver reportedly called for major re-writes of the script shortly before shooting began. Many of the actors had signed up based on the original script, titled "Chimera", which contained far less violence and supernatural elements, and instead was a psychological drama about what happens to a salvage crew when they are stranded in the middle of the ocean. Much of the cast wasn't informed that the script had been almost completely altered into a more generic supernatural-horror/slasher film until just before they showed up to begin filming, leaving many of them disheartened and disgruntled.