The CW's Legend of Tomorrow has added a new recurring role to finish out its fourth season. Hawaii 5-0 actress Sisa Grey is joining the ensemble of time-hopping heroes as the were-creature alter ego of Mona Wu, Wolfie, unveiled in the midseason premiere.

Wolfie is the dual personality of reluctant Time Bureau worker Mona, played by Ramona Young. Now that Care of Magical Creatures assistant has turned into a creature of folklore herself, Mona must deal with a side of herself that represents what she keeps repressed.

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But Wolfie comes to help the Legends just in time, as Hank Heywood's (Thomas F. Wilson) agenda, and what it means for Magical Creatures, is revealed.

Grey is a singer, actress, writer and stage performer whose credits also include SMILF, Grey’s Anatomy, Bosch and I Am the Night.

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Legend of Tomorrow has made recurring characters out of secondary players from its very beginning. Brandon Routh, Caity Lotz, Wentworth Miller and Matt Ryan were frequent guest stars on fellow CW dramas Arrow and The Flash before landing roles on Legends. The game was upped this season with the casting of Thomas F. Wilson (best known as Biff Tannen in the Back to the Future trilogy) as the main villain.

Airing Mondays at 8 pm ET/PT on The CW, DC’s Legends of Tomorrow stars Caity Lotz, Dominic Purcell, Brandon Routh, Nick Zano, Maisie Richardson-Sellers, Tala Ashe, Matt Ryan, Jes Macallan and Courtney Ford.

(via Deadline)