Gaminara plays Dr Richard Locke in the long-running radio soap opera, The Archers. He also voices audiobooks, including Bernard Cornwell's Sharpe novels. His other television credits include Will Newman in Attachments and Dr Andrew Bower in Casualty. Away from acting, he wrote the screenplay for the BBC adaptation of Rachel Morris's novel, Ella and the Mothers. His most notable role was Professor Leo Dalton in the BBC crime drama series Silent Witness, playing the part from 2002 until the death of his character in 2013. He played the part once more in 2017 in the final episode of series 20.