She is of British and Nigerian descent.
Jumbo wrote and starred in a one-woman show, Josephine and I. She won the Ian Charleson Award for playing Rosalind in As You Like It and received an Olivier nomination for playing Mark Antony in an all-female cast of Julius Caesar. She is known for playing Lois Habiba on Torchwood, Becky on Lip Service, Damaris Clarke on Getting On, DC Bethany Whelan on Vera. Cush is widely known for playing the role of Lucca Quinn on the ABC series The Good Wife and it's spin-off The Good Fight.