Ruth Traill

Ruth the Betrayer; or, The Female Spy, by Edward Ellis was the first fictional female detective. It was published by John Dicks as a penny dreadful, in 51 parts, one a double issue; the British Library's single-volume compilation copy was acquired on 28 February 1863, so that it predates Andrew Forrester's The Female Detective and W.S. Hayward's The Revelations of a Lady Detective, both of 1863/4.

Ruth Trail, the protagonist, is "a female detective – a sort of spy we use in the hanky-panky way when a man would be too clumsy".