Epic drama The Inheritance and musicals Come From Away and Company were the big winners at the Olivier Awards on Sunday, receiving four trophies apiece.
Come From Away, inspired by a small Canadian town that sheltered thousands of stranded airline passengers after the 9/11 attacks, was named best new musical at Britain's equivalent of Broadway's Tony Awards. The play also took trophies for sound, outstanding achievement in music and choreography.
Choreographer Kelly Devine dedicated the award in her category to the people of Gander, Newfoundland, who in real life "effortlessly showed the world how easy it is to be kind".
The award for best musical revival went to a production of Stephen Sondheim's Company that gender-swapped the lead role of a commitment-shy New York singleton and turned the usually male Bobby character into Bobbie.
Director Marianne Elliott attributed the show's success partly to "a wind of change blowing in the industry, where celebrating female stories is not only possible, but absolutely vital".
Company also delivered a supporting actress prize to Broadway diva Patti LuPone and a supporting actor trophy to Jonathan Bailey. It took another award for set-design.
The Inheritance, Matthew Lopez's drama about young men living in New York a generation after the Aids crisis was declared best new play.
Lopez said he was "overwhelmed and overjoyed" by the trans-Atlantic success of his seven-hour epic, which had its world premiere at London's Young Vic Theatre.
"We've seen a lot of Brits come over and take home Tonys," Lopez said backstage, clutching a statuette topped with a bust of the late actor for whom the award is named, Laurence Olivier. "It's only fair."
Lopez said he was hopeful the show would get a Broadway run now that London has shown the play resonates with audiences.
The Inheritance also took prizes for lighting and for Stephen Daldry's direction, while star Kyle Soller beat rivals who included Ian McKellen to be garlanded best actor in a play.
Spanish-British actress Patsy Ferran was crowned best actress in a play as a woman consumed by love in Tennessee Williams's smouldering Summer and Smoke. The competition was a talented field that included Gillian Anderson for All About Eve and Sophie Okonedo for Antony and Cleopatra.
Summer and Smoke also took the prize for best revival.
Sharon D Clarke was named best actress in a musical for her powerful performance as the maid to a Southern US family in the 1960s in Tony Kushner's Caroline, or Change. Best actor in a musical went to Kobna Holdbrook-Smith for playing a charismatic, abusive Ike Turner in Tina - The Tina Turner Musical.
Founded in 1976, the Olivier Awards honour achievements in London theatre, musicals, dance and opera. Winners in most categories are chosen by a panel of stage professionals and theatergoers.
Sally Field, Kelsey Grammer, Tom Hiddleston, David Suchet and Gloria Estefan were among the stars walking the red carpet before the ceremony at the Royal Albert Hall.
The show saluted long-running musicals The Lion King and Mamma Mia, both celebrating 20 years of playing in London's West End.
Matthew Bourne – the choreographer behind an iconic all-male production of Swan Lake – received a lifetime achievement honour, presented by Camilla, the Duchess of Cornwall.