Benjamin, in a publicity shot as Celeste Rivers.
Floella Benjamin, Baroness Benjamin (born 23 September 1949) played Professor Rivers in The Sarah Jane Adventures episodes The Lost Boy, The Day of the Clown, The Eternity Trap and Sky.
A Liberal Democrat life peer, she became the first British peer to appear in a Doctor Who production. The second was Tim Bentinck, the 12th Earl of Portland.