The book, which is a sequel to "Red Carpets and Other Banana Skins" and includes a detailed account of Everett's Broadway run in Blithe Spirit and his friendship with the late Tony-winning actress Natasha Richardson (who came to see that production a week before she died), won the prize from a shortlist that also included Simon Callow's "Charles Dickens and The Great Theatre of The World," Arthur Laurents' "The Rest Of The Story," Michael Pennington's "Sweet William," Sue Prideaux's "Strindberg, A Life" and Kate Bassett's "In Two Minds: A Biography Of Jonathan Miller."

Everett collected his award at a ceremony held at London's Garrick Club Feb. 27. Now in its sixth year, the prize is awarded for the best biography, autobiography or diary in theatre or show business published in the preceding calendar year. It was established in 2008 to honor the late Sheridan Morley’s career as an author who specialized in biographies of actors, directors, and theatre and film personalities, including his own acclaimed memoir "Asking for Trouble." In his lifetime, he wrote 37 books, the majority of which were biographies, among them, the authorized lives of Sir John Gielgud, Sir Noel Coward and David Niven. He was also a prolific theatre critic and journalist, including for Playbill.

This year's jury  — chaired by Ruth Leon, Morley's widow and another Playbill contributor — comprised Playbill London correspondent Mark Shenton (also currently chairman of the theatre section of the Critics' Circle and theatre critic for the Sunday Express and contributor of a daily online column for The Stage), Braham Murray (director and founding  artistic director of the Royal Exchange in Manchester) and Isla Blair (actress and writer, whose book "A Tiger's Wedding" was shortlisted for last year's award).

In a press statement, the jury said of Everett's book, "It has been an extraordinary year for theatre biographies, but even in a very strong field, Rupert Everett's 'Vanished Years' was a clear winner. It's just plain fun to read, and is a firsthand account of the everyday life of a working and highly successful actor from the inside. Surprising, hilarious and wise."

Everett received a £2,000 cash prize. The Sheridan Morley Prize for Theatre Biography is a Charitable Trust. It is funded by small donations from individuals and generous support from The Garrick Club, where the awards ceremony is hosted. For further details, visit thesheridanmorleyprize.org.