Gillian Anderson, Joanna Lumley, John Bishop and Damian Lewis are among the stars appearing in a new play – without having rehearsed or seen a script – at London’s Park Theatre this summer.

Whodunnit (Unrehearsed) will see a different guest performer step onstage each night with a rehearsed ensemble cast of a scripted murder mystery play, despite not having had any direction prior to their appearance.

The only direction will come via a hidden earpiece to receive instructions as they attempt to solve the crime in real time.

Whodunnit (Unrehearsed)
Whodunnit (Unrehearsed) (Park Theatre)

Described as a “murder mystery spoof” with “one hell of a twist”, the play is set in an isolated manor against the backdrop of a brewing storm.

Whodunnit (Unrehearsed) will be narrated by Sir Ian McKellen and Dame Judi Dench as a different celebrity appears each night.

Others confirmed to be taking part include Gyles Brandreth, Catherine Tate, Jim Broadbent, Simon Callow, Ronan Keating, Maureen Lipman, Juliet Stevenson, Tim Vine and Meera Syal.

Audiences will only discover which VIP star is performing when they appear onstage.

Joanna Lumley
Joanna Lumley is one of the stars appearing in Park Theatre’s charity show this summer (Ian West/PA)

The stars are donating their time to support a fundraising effort, with money raised going towards the cost of keeping the Park Theatre – a registered charity – open to the public.

Anderson said: “I’m performing at Park Theatre to help raise funds for the charity. With no public subsidy, they need to fundraise over £250,000 a year just to keep the doors open.

“The monies raised from this production’s higher ticket prices will support their core ambition to present accessible theatre over the coming years and to further their work with the local community.

“A number of £10 day tickets will also be available. I do hope people will come and enjoy, and reap the benefit of supporting this fantastic cause.”

Sir Ian McKellen
Sir Ian McKellen will narrate the play (Ian West/PA)

Artistic director Jez Bond said: “We’re very fortunate that the leading actors in our country understand the power and importance of smaller-scale theatres and the challenges they face.

“Performing across the run are a mixture of those who’ve supported us since the building was a hard-hat site and those who’ve come to know us more recently.

“I am grateful to everyone who has donated their time to help raise vital funds by performing this show – and am thrilled they’re so up for it!”

Whodunnit (Unrehearsed) will have a two-week run at Park Theatre before transferring to the Edinburgh Festival Fringe, where further guests will be announced.

Tickets cost between £44-£85, with £10 standing room tickets, for the Park Theatre shows, which will run from July 15-July 27.

It will be at Edinburgh Festival Fringe from July 31-August 26, where tickets start at £10.