Knox made her professional stage debut in 1962 at the Oldham Coliseum Theatre, had a small role as a dancer in the 1969 remake of "Goodbye, Mr. Chips" and appeared opposite Ken Dodd in his 1972 comedy series "Funny You Should Say That". She won the 1989 TV Times Award for Best Actress for one of her best remembered storylines, involving the Alan Bradley character. In 2006, she won the British Soap Award for Best On-Screen Partnership with Malcolm Hebden, having previously received the Lifetime Achievement Award at the 2004 ceremony. She was made an MBE in the 2010 Queen's Birthday Honours.