The latest episode of NBC's "Grimm" promises to be exciting and intense as Nick and Hank investigate a case of demonic possession.

In the upcoming episode, which is titled "Stories We Tell Our Young," Nick faces his toughest challenge thus far when he and Hank investigate a case that combines religious phenomenon, demons and the dark dealings of the Wesen Council. In the meantime, Rosalee is torn because Nick's case challenges her Wesen loyalties. In addition, Captain Renard will head to Europe in order to deal with "family matters."

The synopsis for "Grimm" S3E6, notes that "a young boy's ailments lead everyone to think they are dealing with a case of demon possession," according to Hypable.com.

Some of the stars featured in the episode include, Bitsie Tulloch, Silas Weir Mitchell, Reggie Lee and Claire Coffee.

TVLine has learned exclusive information regarding Monroe's parents, who will be introduced on the show later this season. Dee Wallace from "E.T. the Extraterrestrial" and Chris Mulkey of "Friday Night Lights" will play the Wesen's mom and dad, Alice and Bart.

Before the season began, series co-creator/executive producers David Greenwalt revealed to TVLine that the clock enthusiast's folks would make an appearance related to Monroe and Rosalee's wedding.

"They're a little old-fashioned," Greenwalt warned, implying that Monroe's purist folks may not approve of their son being romantically involved with a Fuchsbau, in addition to being friends with a Grimm. As a result, Monroe must convince his parents to open up to his way of life or risk destroying his relationship with them.

"The Stories We Tell Our Young" is scheduled to air on Dec. 6 at 9 p.m. EST on NBC.