Cynthia Addai-Robinson (born January 12, 1985) is an English-American actress. She is known for her roles as Naevia in the television series Spartacus, DC Comics character Amanda Waller in The CW TV series Arrow, and Nadine Memphis in the USA Network series Shooter. She plays the role of Tar-Míriel on the Amazon Prime The Lord of the Rings series The Rings of Power.