Rhona Natasha Mitra (born August 9, 1976) is a British actress, model and singer.

Mitra is known for her roles as Sonja in Underworld: Rise of the Lycans (2009); as Major Rachel Dalton on the second and third seasons of Strike Back (2012–2013); as Rachel Scott in the first two seasons of The Last Ship (2014–2015); Holly Marie Begins on the sixth season of Party of Five (1999–2000); as Kate Hedges in Ali G Indahouse (2002); as Tara Wilson on the final season of The Practice (2003–2004) and the first and second seasons of Boston Legal (2004–2005); as Detective Kit McGraw on the third season of Nip/Tuck (2005); in the lead role of the science fiction/action film Doomsday as Major Eden Sinclair (2008); as an assassin in the Netflix film Game Over, Man! (2018); and as Mercy Graves in the CW series Supergirl (2018).

Early life
Rhona Mitra was born in 1976 or 1977 in the Paddington area of London, the daughter of Anthony Mitra, a surgeon, and Nora Downey. Her father is of Bengali Indian descent, while her mother is Irish.