As part of Britain's most famous acting dynasty, Lynn Redgrave seems to lead a blessed existence, but no amount of money or fame could have softened the blows the fates have dealt her.

The painful breakdown of her marriage in 1999 was followed by a severe case of breast cancer in 2002, yet out of this darkness came Nightingale, a new play by Redgrave which receives its European premiere at Richmond's Orange Tree Theatre this Sunday.

The piece, inspired by memories of her maternal grandmother Beatrice "Beanie" Kempson, originated when Redgrave was recuperating from her divorce at her sister Vanessa's house in Chiswick.

Tired and emotional, Redgrave decided to take an early morning walk to the local churchyard of St Nicholas to look for her grandparents' graves, only to discover the headstones destroyed by acid rain.

"To find their names erased at a time when I was desperately clinging to my roots was completely devastating to me," recalls Redgrave, speaking from her home in Connecticut.

"It got me thinking: What happens to us once we've gone if we haven't done something to leave a mark? When Vanessa, Corin and I are dead, who will remember our grandmother Beanie?"

Redgrave, who reveals that learning she had cancer was "like being given a death sentence", was moved to write what she describes as a jazz musician's riff on the few facts she knew about her grandmother's life.

With Beatrice's name changed to Mildred, the riff expanded into a one-woman play and Redgrave knew immediately that her lifelong friend and fellow actress Caroline John would play that woman.

Contemporaries at the Central School of Speech and Drama, Redgrave and John have lived mirrored lives ever since and when Redgrave was diagnosed with cancer, it was John who caught a plane over to the US and nursed her through the operation, without knowing that she would be diagnosed with cancer herself just six months later.

Nightingale is Redgrave's thank you gift for her friend's support.

"As female actors, the opportunities to show the range of what a life in the theatre has taught us become fewer and fewer as we grow older," she explains.

Since winning the Golden Globe for Best Supporting Actress in 1999's Gods and Monster, Redgrave has appeared in more than 20 films and next up is the choice role of Lady Bracknell in a Los Angeles stage production of The Importance of Being Earnest.

Her father Michael Redgrave played Jack in the 1952 film version and Redgrave is looking forward to stamping her own mark on a part made famous by dames Margaret Evans and Judi Dench.

  • Nightingale, Orange Tree Theatre, 1 Clarence St, Richmond, Sunday September 18, 7pm followed by a post-show discussion with the author, £8-£10, 020 8940 3633,