ABC has released the plot synopsis for the upcoming first episode of a two-part arc of Castle, which will see the return of 3XK (Michael Mosley).

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Episode 7.14 of Castle is titled Resurrection and it is slated to bring Castle (Nathan Fillion) and Beckett (Stana Katic) back into the world of 3XK and Dr. Kelly Nieman (Annie Wersching).

"When clues in a murder implicate Castle and Beckett's nemesis, Dr. Kelly Nieman (guest star Annie Wersching), Castle is called in to consult on the case," the synopsis for the episode reads. "But as the team delves deeper into the investigation, they uncover connections to notorious serial killer Jerry Tyson (guest star Michael Mosley)."

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As previously mentioned, Wersching and Mosley will reprise their respective roles, while other guest stars include Laura Coover as Susan Watts, Amy Rosoff as Katrina and Maya Goodwin as Laura.

This episode is slated to air Monday, Feb. 9 at 10 p.m. ET/PT on ABC. Part 2 of this arc will air the following Monday on Feb. 16.

Castle show runner David Amann previously spoke to Entertainment Weekly about the return of Dr. Nieman, saying that the episode should be a fun one.

He said that Neiman's possible involvement in the murder "puts us on what we think is going to be a fun, dramatic journey for the audience as we try to solve that murder and figure out what her involvement is in it, if any."

Castle airs Mondays at 10 p.m. ET/PT on ABC.

Watch the promo for the next episode of Castle below: