Nicole Kidman battled with nerves before accepting stage role
Nicole Kidman said she suffered from "terrifying" nerves getting back on the stage after 17 years.
She won the gong for best actress in a play for her part in Photograph 51, which also picked up the top slot for best new play at the WhatsOnStage Awards.
"It's so fulfilling but it was terrifying," she added.
"The stage fright was pretty extreme, I had it pretty badly."
The 48-year-old said she took the role for her biochemist father Antony, who died last September.
"I had an emotional need for this performance because of my dad.
"I've had a lot of scientists come and say thank you."
She described her character, British scientist Rosalind Franklin, as "unusual, prickly and complicated but very pure".
Kidman said she is looking forward to her next role alongside Reese Witherspoon in TV series Big Little Lies, based on the novel by Liane Moriarty.
"One of the reasons I'm so excited is it's written by a female," she added.
"The five leads are all played by women too."
Benedict Cumberbatch was named best actor in a play for his portrayal of Hamlet, which also won in three other categories.
The blockbuster production of the Shakespeare classic at the Barbican was also named best play revival, best set design and best lighting design.
The winners, decided by a vote of theatregoers and announced at a ceremony at the Prince of Wales Theatre in central London, also included Dame Judi Dench who won best supporting actress in a play for her work in The Winter's Tale.
Matt Henry bagged best actor in a musical for Kinky Boots, which was also voted best new musical, while Imelda Staunton won best actress in a musical for Gypsy, which also came top in three other categories.
The best West End show went to Les Miserables.
Mark Gatiss, who won best supporting actor in a play for his role in Three Days In The Country, said the Sherlock cast are "a family" and described the show as "life changing".
"We start filming Sherlock in April, three more episodes," he added.
"It will be out next year, so only a year to wait.
"We're a family, we've done seven years now - it's a hell of a long time.
"It's an incredible worldwide success, it's been life-changing."
He said winning the award was "delightful and a complete surprise".
Gatiss described Cumberbatch as "wonderful as Hamlet" and added: "The response to it is astonishing."