The upcoming "Supernatural" Season 12 episode 15 is titled "Somewhere Between Heaven and Hell." The Winchester brothers will face a creature from Hell.

The most recent spoiler of "Supernatural" Season 12 episode 15 teased of Sam (Jared Padalecki) and Dean's (Jensen Ackles) mission to stop an invisible Hellhound. On the other hand, Crowley's (Mark A. Sheppard) most kept secret will be revealed.

The Winchester brothers' new mission will force them to collaborate with Crowley as the team scrutinizes an attack that was made by an invisible hound from Hell. The scene of the crime was a campsite with one female camper serving as the only witness to the hellish beast's rage. The mysterious creature, however, will be a tough opponent for the Winchester brothers. This was highlighted in the "Supernatural" Season 12 episode 15 promo clip posted on Spoilers Guide.

Crowley, in the teaser, said that Sam and Dean would have to deal with one of hell's perilous creatures, the Hellhound. With Crowley's warning, it is apparent that the beast is not an ordinary hellish creature. The upcoming "Supernatural" Season 12 episode 15 will be another fierce battle with The King of Hell further underlining that the main characters will have to deal with THE Hellhound.

Viewers can also expect that the upcoming "Supernatural" Season 12 episode 15 will stage a very intense, yet interesting encounters between Crowley and Lucifer (Mark Pellegrino). Sam and Dean overpowered the fallen angel, Lucifer, which was succeeded by Crowley's attempt to keep Lucifer locked up in a room on chains. The Hell's ruler will continue to keep the devil's imprisonment concealed from other demons. Several of Crowley's personal demons, learning about what their King has been hiding, will soon discover this sensitive information. The discovery could lead to Lucifer's escape in the forthcoming episode.