Supernatural's Darkness is far from the only insidious force mounting against the Winchester brothers. Rowena is back, and the crafty witch's machinations are about to come to fruition.

The CW spooker is racing towards the season 11 finale, and, in the wake of "The Chitters," Sam (Jared Padalecki) and Dean (Jensen Ackles) are officially off monster-of-the-week cases. Starting with "Don't Call Me Shurley," the hunters will turn their attention exclusively towards the season's overarching mythos.

When episode 22, "We Happy Few," rolls around, Rowena (Ruth Connell) will be back in the picture.

"Sam and Dean face their biggest challenge yet," The CW teased. "Rowena makes her move."

Skimpy description, we know. Shows generally double down on their secrecy as finale season approaches, usually in an effort to preserve a few jaw dropping twists. A couple of behind-the-scenes photos and videos, however, have helped elucidate the episode 22 situation. Rowena won't be the only guest on hand - Chuck (Rob Benedict) will also appear. Castiel (Misha Collins) will join the chaos as well, and, although it hasn't been confirmed, we strongly suspect that Amara (Emily Swallow) will have a role to play.

While fans await the penultimate episode, Supernatural will air "Don't Call Me Shurley" on May 4 and "All in the Family" on May 11. Check out the summary below to find out what's in store for this Wednesday's hour:

Amara unleashes a dark fog on a small town, causing everyone to go mad. Dean and Sam realize this is a stronger version of the original black vein virus Amara previously unleashed. They team up with the sheriff to protect the town but their old remedy no longer works," The CW teased. "Meanwhile, Chuck returns with an interesting proposal."

Supernatural airs Wednesdays at 9 p.m. ET on The CW. Click the video below to see a preview for the series' next episode.

Tags: supernatural television the cw