As a child, Mills appeared as an extra in various films, including a role as Freda's 11-week-old baby in the 1942 film
In Which We Serve, starring her father. In 1955, aged 14, while boarding at Elmhurst Ballet School, she appeared in a starring role as
Alice in a London stage production of
Alice Through the Looking Glass at the Chelsea Palace Theatre. Her first major film role came in 1958, when she was 16, as Pamela Harrington in the
Peter Shaffer play
Five Finger Exercise. The show ran one year in London, and then moved to the
Music Box Theatre on Broadway. In 1960, Mills was nominated for a
Tony Award as "Best Featured Actress" for her performance as Pamela. In 1961, Mills appeared as a stowaway, dressed as a man but the daughter of a ship's gunner, in episode 2 of
Sir Francis Drake. This was one of her first TV appearances, and was echoed by an almost identical role in the 1964 film
Carry On Jack. '' In the 1960s, Mills would appear both in films and on television. She had a role in the film,
The Rare Breed with
James Stewart and
Maureen O'Hara, and on television series such as
The Man from U.N.C.L.E.,
Ben Casey and ''
12 O'Clock High. She has stated that the highlight of her film career was Avanti! (1972), directed by Billy Wilder, in which she starred opposite Jack Lemmon and for which she received a Golden Globe Award nomination in 1973. In 1974, Mills starred alongside fellow English actor Richard Johnson in the Italian horror film Beyond the Door, playing the role of Jessica Barrett, a woman who becomes demonically possessed after an unplanned pregnancy. The movie was a major success, making over $15 million at the box office, though the producers were sued by Warner Bros due to similarities to The Exorcist. Mills also appeared in a two-part 1978 episode of the TV series The Love Boat'', playing Barbara Danver, wife of Alan Danver, played by
Dan Rowan. ,
David Doremus,
Trent Lehman,
Kim Richards and Mills In 1969, Mills was cast in the American television series
Nanny and the Professor, which premiered on ABC in January, 1970. Mills played Phoebe Figalilly, a nanny with seemingly magical powers, reminiscent of
Mary Poppins. Mills has stated that she herself believes in magic, witches and fairies: "There's a lot more, you know, in the
aether and around us ... We have guides, and we have angels taking care of us ... I believe in
metaphysics, in a big way." Mills was nominated for her first
Daytime Emmy Award for "Outstanding Lead Actress" for the role.
Passions ended in August, 2008. In 2009, Mills joined the cast the
ITV drama
Wild at Heart, playing Georgina, the sister of a character played in the previous series by her real-life sister Hayley. She also guest-starred in two episodes of
Hot in Cleveland as Philipa Scroggs, the mother of Joy (played by
Jane Leeves). ==Personal life==