O'Mara was one of the best-known actresses of her generation, famous for playing a succession of power-hungry and ruthless women in some of the most iconic television dramas of the 20th century.
Born in 1939, the daughter of actress Hazel Bainbridge and RAF flying instructor John F Carroll, she made her stage debut in 1963 in a performance of The Merchant of Venice. The following year she began her television career which led to guest roles in series such as Danger Man, Adam Adamant Lives!, The Saint, Z-Cars and The Avengers.
In 1975 she was cast as Jane Maxwell in the BBC's Sunday night drama The Brothers, playing alongside Colin Baker. Appearing in 30 episodes, her portrayal of the tough, uncompromising businesswoman would define the roles she would play throughout her career.
In 1982 she joined Triangle, the notorious early-evening soap opera, filmed on a North Sea ferry, playing Katherine Laker. Hollywood called in 1986 when she was cast as Caress Morrell, the younger sister of Joan Collins, in the American series Dynasty. Back in the UK, she starred in Howard's Way, Crossroads and Bad Girls.
Her fame led to guest appearances on such shows as Morecambe and Wise, The Two Ronnies and Absolutely Fabulous.
In 1985 John Nathan-Turner reunited O'Mara with Colin Baker, when he asked her to take on the role of The Rani in the Sixth Doctor story The Mark of the Rani. Her character was so successful she returned in 1987 in the first story of the Seventh Doctor, Time and the Rani, a script which required her to impersonate the Doctor's then companion Mel, played by Bonnie Langford. Her final appearance as The Rani came in 1993, when she appeared in the Children in Need spoof set in the world of EastEnders, Dimensions in Time.
Last year she spoke to Digital Spy about her work on Doctor Who:
If you put a much older woman in Doctor Who, they can identify with it. I think it's quite an interesting concept and if you remember things like Grimm's Fairytales, the older woman is often the villainess, often the terrifying figure - why I do not know, but often she is. I think it's an idea to be exploited.Stars have taken to Twitter to pay tribute. Colin Baker said: "Oh my goodness. Kate O'Mara is no longer with us. Sad sad news. A delightful, committed and talented lady and actress. We are the poorer", with Bonnie Langford adding: "So sad to hear that the wonderful Kate O'Mara has gone. Treasured memories xxx". Nicola Bryant said: "Such sad news:Kate O'Mara is no longer with us. A charismatic, courageous, & caring soul; a wonderful actor & a friend. May she finally RIP." while Dynasty co-star Joan Collins added: "Tragic news about Kate O'Mara , we had great fun on Dynasty when she played my sister Caress... RIP". Tracey Childs, who worked with O'Mara on Howards' Way, said: "Today the world lost a fine actress & dedicated producer & I lost a friend of 3 decades. Safe journey Kate O'Mara. You were an inspiration X".
O'Mara died in a Sussex nursing home following a short illness. She was married twice, both times to actors, firstly to Jeremy Young and then to Richard Willis, and leaves a sister, actress Belinda Carroll, and a son, Christopher Linde. Her first son, Dickon Young, died in 2012.
The actress last posted a message on Twitter on 17 March, to say:
Thank you so much for your kind tweets. It's both humbling and completely overwhelming to read all of your messages. Much Love x.