During the night, the dog mutates and attacks other dogs in the cage and members of the team that investigate. The team soon realises that an alien life-form with the ability to take over other bodies is on the loose and they don't know who may already have been taken over. John Carpenter is a great concept director - he comes up with some brilliant story ideas which sound great on paper. In terms of a film though its good but not up to the potential it should've been. The early 80's low-budget feel unfortunately hinders the story and the paranoia aspects seem old, yet the introduction is nice and different and there's still some 'which one is it' sequences that are good.
Trouble is the explosive gore substitutes for real suspense.
Russell isn't memorable at all here, as aren't any of the other actors. The film itself is good quality, but the harsh arctic scenery and lighting don't work well on ordinary TV screens. For an early 80's film there's a LOT here and worth getting by any Carpenter fan.