We have the synopsis for Supernatural season 14 episode 5.
 
SUPERNATURAL
“Nightmare Logic” — (8:00-9:00 p.m. ET) (TV-14, LV) (HDTV)

DARE TO DREAM – After a hunt gone wrong leaves Maggie’s (guest star Katherine Evans) whereabouts unknown, Sam (Jared Padalecki) Dean (Jensen Ackles), Mary (guest star Samantha Smith) and Bobby (guest star Jim Beaver) race to find her, but what they find are their own worst nightmares. Darren Grant directed the episode written by Meredith Glynn (#1405). Original airdate 11/8/2018.

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Maggie's missing? What kind of nightmares do you think Sam, Dean, Mary and Bobby will have? Let us know in the comments or in the discussion thread for episode 5.