From Wikipedia, the free encyclopedia. Rosemary Leach (18 December 1935 – 21 October 2017) was a British stage, television and film actress and singer. She was born at Much Wenlock, Shropshire. Her parents were teachers related to Edmund Leach. She attended grammar school and RADA. After appearing in repertory theatres and the Old Vic she became well known to UK TV viewers between 1965-69 for playing Susan Wheldon, the mistress of building tycoon John Wilder (Patrick Wymark) in the TV boardroo...