When a patient, Kenny, shows up at her home unexpectedly, Dr. Joanna Redding attempts to help him overcome his "irrational" phobia of the creatures that he sees in his peripheral vision. Dr. Redding uses Exposure Therapy, forcing Kenny to face his fear. Of course, the creatures that terrify Kenny are very real - and very deadly. It is a horrifying discovery that Dr. Redding uncovers all too late.