Bobby Vega's kid sister Sally is missing. She is number twelve.
When a local mute Native American handyman, Joe White Eagle, is accused of being behind the disappearances of numerous children, Bobby knows something is amiss. Joe is his friend, and Bobby isn't the only one who suspects someone, or something else, took Sally. Detective John Redbird still grieves the day his own child went missing and wonders if the two incidents are connected.
Joe confesses that he knows where Sally is - a place he was once held captive in as a child. A place known as THE DIM, a shadowy in-between world only a child can enter. A place of unspeakable terror.
To rescue Sally, Bobby must find the courage to recreate a ritual he sees Joe perform that opens the door between worlds. Once inside, he uses a map left by Joe to navigate a dizzying realm of hallways, doors, and rooms filled with booby traps and monstrous entities that all lead to the lair of the Wiggle Man, the interdimensional ruler of THE DIM. Bobby rescues Sally and the missing children and escapes, only to discover that hundreds more children are trapped deep within THE DIM, and their time is running out.
Bobby knows he must return to THE DIM, accompanied this time by 12 brave child warriors, including a human/demon hybrid with a shocking link to Detective Redbird. This time he has allies; an army of wolves and crows sent by Joe White Eagle and a flying foul-mouthed, big-hearted hag named Sharlene.
Bobby and his warriors race against time to rescue the children from a horrifying fate at the hands of the Wiggle Man. But can they escape in time and close the door to THE DIM - or will they be lost inside forever?