Lawless is best known for playing Xena in Xena: Warrior Princess, but also for roles in Battlestar Galactica and Spartacus. Her character, Hartley, is a veteran S.H.I.E.L.D. agent who joins up with Director Coulson to help him rebuild the organization after last season's revelation that it had been infiltrated by Hydra.
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Agents of S.H.I.E.L.D. Season 2 premiers September 23 on ABC.