Spirit of Television - S3.E18

A psychic medium is dying of a rare degenerative disease. She stumbles upon a cursed television set, which allows her to put her customers in contact with the spirits of their dearly departed. Besides being paid a hefty fee for these real manifestations, she also gets a temporary 10-day extension of her life. The curse later sends the same spirits, horribly twisted and vengeful, after their ""loved one"" and kill them. The trio notice the pattern of deaths and a friend of Jack's tries to debunk the medium's powers. Eventually he commits suicide rather then let the spirits claim him, and the failure to follow through means the medium dies too.