Supernatural - S08E06 - Southern Comfort

Sam and Dean investigate a murder and find Garth is already on the case. Dean is not happy to learn that Garth has assumed Bobby’s duties, but Garth points out that both Sam and Dean have been missing for the last year and someone needed to do it. They guys discover an “avenging ghost” is responsible for the murders and they need to find the source before the killings starts again.