Emma and Jesse are living the perfect life together, until Jesse disappears in a tragic helicopter crash on their first wedding anniversary. Four years later, Emma has found happiness again and is about to marry her best friend when Jesse resurfaces, turning her world upside down and leaving her torn between two great loves.

Survivors escape to a deserted atoll, after their boat during a Semester at Sea ship is sunk by a mutated two-headed shark. But when the atoll starts flooding, no one is safe from the double jaws of the monster.

A young couple plans to have a rockabilly themed wedding out at the old farm, despite warnings of a West Nile Virus outbreak. Things go horribly wrong when the virus spawns zombie-creating mosquitoes, who begin to feed on the wedding guests.