Benny Andersson and Bjorn Ulvaeus performed with the cast of 'Mamma Mia!' at the Olivier Awards with MasterCard last night (13.04.14).
The ABBA stars took to the stage at London's Royal Opera House to sing 'Thank You For the Music' with stars from the musical - which is based on their group's hits - in the evening's finale, a medley of songs from the production, which is celebrating 15 years in the West End.
Earlier in the evening, 'Chimerica' and 'Book of Mormon' were the big winners at the ceremony, which honours outstanding work in theatre, opera and dance, taking home five and four prizes respectively.
Lucy Kirkwood's play took home the American Airlines Best New Play, Best Director for Lyndsey Turner and the XL Video Award for Best Set Design for Es Devlin,.
Tim Lutkin and Finn Ross shared the White Light Award for Best Lighting Design with Paul Pyant and Jon Driscoll for 'Charlie And The Chocolate Factory', and Carolyn Downing jointly won Best Sound for 'Chimerica' along with Gareth Owen for 'Merrily We Roll Along'.
'The Book of Mormon' - which is written by 'South Park' creators Matt Stone and Trey Parker - scooped MasterCard Best New Musical, Best Actor in a Musical for Gavin Creel, Best Performance in a Supporting Role in a Musical for Stephen Ashfield and Best Theatre Choreographer for Casey Nicholaw.
Meanwhile, Lesley Manville beat off competition from Dame Judi Dench, Anna Chancellor and Hayley Atwell to pick up Best Actress for her performance in 'Ghosts', and Jude Law, Tom Hiddleston and Henry Goodman lost out to 'Othello' actor Rory Kinnear in the Best Actor category.
Kate Moss made a surprise appearance at the ceremony, to present theatre impresario Michael White with a Special Award for outstanding achievement alongside Nigel Planer, and James Corden and Best Actor winner Rory handed another of the honours to the National Theatre's Sir Nicholas Hytner and Nick Starr.
Other performers at the awards - which were hosted by Gemma Arterton and Stephen Mangan - included legendary Broadway star Bernadette Peters and opera singer Joseph Calleja, while there were musical numbers from all the nominated productions in both the MasterCard Best New Musical and BBC Radio 2 Audience Award categories, including winners 'The Book of Mormon' and 'Les Miserables' respectively.
Olivier Awards with Mastercard 2014 full list of winners:
American Airlines Best New Play: 'Chimerica'
MasterCard Best New Musical: 'The Book of Mormon'
Best New Comedy: 'Jeeves and Wooster in Perfect Nonsense'
Best Entertainment: 'The Wind in the Willows'
Best Revival: 'Ghosts'
Best Musical Revival: 'Merrily We Roll Along'
Best Actress in a Play: Lesley Manville, 'Ghosts'
Best Actor in a Play: Rory Kinnear, 'Othello'
Best Actress in a Musical: Zrinka Cvitesic, 'Once'
Best Actor in a Musical: Gavin Creel, 'The Book of Mormon'
Best Supporting Actor in a Play: Jack Lowden, 'Ghosts'
Best Supporting Actress in a Play: Sharon D. Clarke, 'The Amen Corner'
Best Supporting Performer in a Musical: Stephen Ashfield, 'The Book Of Mormon'
Best Director: Lyndsey Turner, 'Chimerica'
Best Theatre Choreography: Casey Nicholaw, 'The Book Of Mormon'
Outstanding Achievement in Music: Martin Lowe, Glen Hansard and Marketa Irglova, 'Once'
Best New Opera Production: 'Les Vepres Siciliennes,' Royal Opera House
Outstanding Achievement in Opera: English Touring Opera
Best New Dance Production: 'Puz/zle' at Sadler's Wells
Outstanding Achievement in Dance: Michael Hulls for his body of lighting work including 'Ballet Boyz -- The Talent' at Sadler's Wells
XL Video Award for Best Set Design: Es Devlin, 'Chimerica'
While Light Award for Best Lighting Design: Tim Lutkin and Finn Ross, 'Chimerica'; Paul Pyant and Jon Driscoll, 'Charlie And The Chocolate Factory'
Best Sound Design: Carolyn Downing, 'Chimerica'; Gareth Owen, 'Merrily We Roll Along'
Best Costume Design: Mark Thompson, 'Charlie And The Chocolate Factory'
BBC Radio 2 Audience Award: 'Les Miserables'
Outstanding Achievement in an Affiliate Theatre: 'Handbagged,' Tricycle Theatre
Special Awards: Michael White; Nicholas Hytner and Nick Starr