“To be honest, it’s rather daunting thinking about looking back over a whole life! It’s been eventful to say the least!” - so says iconic Welsh actor Dame Siân Phillips.

A new, star-studded documentary film in ‘Siân Phillips yn 90’ will be broadcast on S4C on Friday, December 29 at 9 pm, to mark Siân’s 90th birthday this year.

From Hollywood films to theatre, television and radio, Siân Phillips has done it all.

The star of I, Claudius and ex-wife of Peter O’Toole speaks candidly like never before about her life and career so far.

In this special film, a host of famous faces pay tribute to her, including - Sir Derek Jacobi, Matthew Rhys, Dame Penelope Wilton, Dame Eileen Atkins, Rakie Ayola, Nigel Havers and Daniel Evans.

The journey will take us from London back to her childhood home at the foot of the Black Mountains in West Wales. In the film Siân vividly recalls a life-changing visit to the theatre aged six.

She said: “I thought, this is what I want to do, this is where I want to live, up there under the lights. I thought I was in heaven. And when I got home, I wrote in my diary; ‘I am now resolved to being an actress’.”

From those early days Siân went on to have a glittering, international career that has spanned nine decades.

Her most iconic roles include appearances in I, Claudius, How Green Was My Valley, Dune and Goodbye Mr Chips. But her path to success hasn’t been easy.

In ‘Siân Phillips yn 90’, Siân speaks openly about her tumultuous, 20-year marriage to Peter O’Toole.

“We loved each other deeply, but he could be very cruel” said Siân.

In a heartrending moment, Siân recalls how she missed what she describes as the golden years in an actor’s life between the ages of 28 and 40; years she believes cement an actor’s career.

“I was scared of being too successful all the time,” she says.

“I don’t know why, he [O’Toole] was very threatened by all that. There was no reason for him to be, God knows, but he was insecure.”

Their marriage eventually broke down and they divorced in 1979.

From the early 1980s, Siân had a new lease of life and her career went in a new direction with acclaimed roles in West End musicals.

In 1997, when Siân was in her late 60s, she took on her toughest role yet, that of Marlene Dietrich.

The hit musical, Marlene, was a huge success in London and on Broadway, running for four years.

Sir Derek Jacobi, friend and fellow star of I, Claudius said: “Dame Sian Phillips, she’s up there with all our leading actresses. She has beauty, she has talent. She has huge charisma and is one of those actresses in whose company you are very happy to be.”

In the film we follow Siân as she rehearses her latest show It’s All Greek with Alex Jennings. Aged 90, her drive to keep working is undimnished.

Dame Eileen Atkins says of her friend: “Behind a lot of huge glamorous success stories is a hard, hard worker. No-one works harder than Siân. Siân Phillips the actress was made in Wales.”

Siân is an internationally acclaimed actress in television and film, but the theatre remains closest to her heart.

“I love the theatre. No matter how badly your day’s going, when you come to the theatre and hear the orchestra, you feel on top of the world. It’s like being home,” says Siân.