Careful with that. . . the drug pusher sometimes ends up having to come to a Supernatural Convention in the addict's home state(s).
Karma!
The King of Hell, from Supernatural was on Leverage as a regular.
That and the other situation he talked about, the amputee phantom pain, both were episodes on House, MD.
Another great show is Major Crimes. I just finished binge watching that and The Closer, which Major Crimes is a spin-off of. I Liked Major Crimes better.

It's more character/team driven, like CM is now. When it was The Closer, it was more like when Gideon was on and the show was more about him and being obsessive about solving cases.
Season 3 is coming back at the end of Nov and they've already been picked up for Season 4.