In a desperate attempt to cling to life, shortly after the terrifying events of Anaconda 3: Offspring (2008), Murdoch enlists the help of a young doctor to harvest the rejuvenating serum of the rare Blood Orchids. Once more, a failed experiment leads to a new reptilian horror, as an ever-growing, genetically enhanced super-serpent breaks free from the laboratory. Now, the dauntless herpetologist, Amanda Hayes, and a handful of scientists must outsmart Murdoch's armed-to-the-teeth henchmen, to have a fighting chance. But, can they put an end to the nightmare of the mutated Anacondas?