The midseason finale of "Supernatural" will find the Winchester brothers in danger as they take on not just one threat to humanity, but two of them as Amara (Emily Swallow), who is now fully grown, has decided to unleash her evil powers to the world while The Darkness continues to be a threat to humanity.

The official synopsis for episode 9, titled "O Brother Where Art Thou?" is as follows:

"Amara unleashes her power on the local townspeople as she issues a shocking challenge. Dean (Jensen Ackles) tries to better understand the hold Amara has on him, while Sam (Jared Padalecki) and Crowley (Mark Sheppard) come up with a plan that could have disastrous consequences."

In photos posted on TV Overmind, it appears that episode 9 will have a lot of challenges and surprises in store for the brothers as the hour sees the return of Rowena (Ruth Connell). As for Sam and Crowley's plan, it looks like Sam will make up his mind and finally go inside the cage where Lucifer (Mark Pellegrino) is being held.

Last week, Sam told his imaginary friend Sully about his visions and how God wanted him to go back to the cage. Sam also told Dean about his plan, but Dean said that there's always another way as he refused to have his brother placed inside a cage with the devil himself.

In the promo clip for "O Brother Where Art Thou?" Sam is praying out loud and asks, "Is this what You want?" Sam gets an answer right away as a bush just a few feet from where he's standing bursts into flames.

"I asked God for a way to beat The Darkness," Sam tells Dean, "And I was in the cage."

"With Lucifer?" Dean asks, incredulous.

Amara is seen unleashing her powers, and at one point, she and Dean start kissing. Lucifer is seen taunting Sam as the devil tells him, "I am your only hope."

The mid-season finale of "Supernatural" airs on Wednesday, Dec. 9 at 9 p.m. on The CW.