'Weeds' Alum to Haunt 'Grimm's' Halloween Episode (Exclusive)

Kate del Castillo will guest star as a mysterious detective who helps capture a serial child abductor in the episode, which will be loosely based on the Mexican legend "La Llorona."
Kate Del Castillo

NBC's Grimm is taking on the case of the Weeping Woman.

Weeds alum Kate del Castillo will pop in to the creepy procedural for the second-year drama's Halloween episode, titled "La Llorona," which is loosely based on the famed legend of a woman who drowned her children.

Castillo, who played Esteban's crafty adviser who Shane whacked with a croquet mallet on the fifth season of Showtime's Weeds, will play Valentina Marquez, a mysterious dectective from Albuquerque who comes to Portland to help Nick (David Giuntoli) and Hank (Russell Hornsby) capture a serial child abductor. Valentina has spent the past five years tracking the perp and identifying patterns in related abductions.

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According to the La Llorona (which translates to weeping woman) legend, a woman named Maria kills her children by drowning them in order to be with the man she loves. Upon his rejection, she commits suicide but is not permitted to enter the afterlife until she finds her missing children, forcing her to wander the Earth for all eternity, crying, as she searches for her drowned offspring.

Del Castillo broke out in Fox Searchlight/Weinstein Co.'s feature Under the Same Moon, which ranks as the top grossing Spanish-language theatrical release in U.S. history. Her crdits also include Telemundo's Queen of the South. She's repped by CAA, Si Entertainment and Felker Toczek.

Grimm airs Fridays at 9 p.m. on NBC.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit