Season 10 episode 17, titled "Inside Man", of the fantasy horror series "Supernatural" will be aired in The CW network on Wednesday, 1 April.
Sam and Castiel, who are firm about finding a cure for the "Mark of Caine", are seeking the help of someone in heaven; and that someone is their old friend and mentor Bobby (Jim Beaver). Dean has a face-off with Rowena (Ruth Connell) on the other side of the world - below the ground - and is seen settling it in "Inside Man".
Towards the end of episode 16, "Paint it Black", Sam (Jared Padelcki) told Dean (Jensen Ackles) that they would anyhow save Dean from the "Mark of Caine" before he went down the path Caine professed - ending with Dean killing Sam. It appears that Castiel (Misha Collins) and Sam will need someone's help in heaven, and who else would they turn to other than Bobby?
Bobby was shot in the head by Leviathan leader Dick Roman (James Patrick Stuart) in Season 7 episode 9, "How to Win Friends and Influence Monsters". However, he spends the next episode, "Death's Door", in a coma before finally dying. His last word was "idjits", a term of endearment he reserved for the Winchester boys. He stayed on as a ghost in the series for another nine episodes before he requests Sam and Dean to finish him before he turns into a vengeful spirit.
Bobby was next seen in Season 8 episode 19, "Taxi Driver", wherein Sam transports him from Hell to Heaven, as part of the second trial to close the Gates of Hell. He was last seen in Season 9 episode 1, "I Think I'm Gonna Like it Here", wherein Bobby was a culmination of Sam's subconscious.
However, in the 1 April episode, the fan-favourite Bobby Singer is going to return. From the looks of it, he may even be a gang-leader of heaven and in a great position to help out his surrogate sons.
Meanwhile, Dean is dealing with Crowley's (Mark Sheppard) mother Rowena, who will definitely make a move against the Winchesters. In the previous episode, she was informed that the brothers are the only two remaining members of the "Men of Letters".
Watch out for Season 10 episode 17, "Inside Man", of "Supernatural" on The CW at 9.00 pm on Wednesday, 1 April.