The sellout opening run of The Mousetrap shows there is “clearly an appetite” for the return of theatre, according to the play’s producer.

Following the easing of coronavirus restrictions on Monday the show, which is billed as the longest-running play in the world, will be put on in front of an audience for the first time since the pandemic closed theatres in March 2020.

The show, running at the St Martin’s Theatre, is approaching its 70th year and has been staged on 28,200 occasions.

Producer Adam Spiegel told the PA news agency: “It’s very exciting to see the building come alive again.

“It’s been 12 months and the theatre has been more or less completely empty and theatres are funny buildings when they are empty.

“They need actors and staff and audiences, so now the countdown is on to actually feeling the building coming alive again and doing what it’s supposed to do.

“We are sold out for the next few weeks, so there’s clearly an appetite to come back to the theatre.

“Obviously we are operating with social distancing, so we have a reduced capacity, but my sense is that people want to get back out.

“They want to go and eat, they want to go to the theatre, they want to go to the cinema, they want to go out of their houses.”

The West End production of The Mousetrap was originally adapted from Agatha Christie’s radio play Three Blind Mice, which was written for the royal family in 1947.

Capacity inside St Martin’s Theatre has been reduced by more than half of its usual limit of 550.

Mousetrap stars Danny Mac and Cassidy Janson (PA)

Spiegel said it is financially “unsustainable” for the theatre to continue to put the show on “long-term” with the reduced capacity.

“We can do it for a while but I hope that while isn’t too long,” he said.

Spiegel said he hopes that after surviving the pandemic The Mousetrap will continue to be put on “beyond my lifespan”.

He added: “It’s 70 next year and I’d like to think we have then got to start planning the 100th, but for the moment let’s just take it one day at a time.”

The Mousetrap features a new company including Strictly Come Dancing star Danny Mac, West End regular Cassidy Janson, soap actors Nicholas Bailey and Charlie Clements, as well as Susan Penhaligon and children’s TV presenter Derek Griffiths.

Mac said he had been “worried about theatres ever being able to open again, because you just start to think the worst”.

He told PA news agency: “At the beginning of lockdown I was like: ‘This will be a few weeks, we will be back shortly.’

“And then time went on and we tried to get back and we didn’t and it was getting worse and worse and I kept thinking: ‘If this keeps going this way, we will never get back.'”

Putting the production on again feels “amazing”, he said, adding: “It feels like we are really part of something right now, and I mean that as a nation, not just us in this show.”

Janson said it has been “traumatising” watching damage done to “the industry that we have dedicated our lives to”.

She said the industry has been “desecrated” and she has been “fighting for people to understand the plight of theatre”.

Theatre boss Lord Lloyd-Webber said people refusing to take up the offer of a coronavirus vaccine were “selfish” as they could hinder the ability to lift all restrictions next month.

The composer said he would not be opening shows in his theatres until all measures are scrapped as they were “too costly” to play to reduced audiences.

The peer told BBC Radio 4’s World At One the June 21 date was “absolutely critical”, adding: “If that doesn’t happen, I really don’t even want to think about it.

“It has been such a devastating time for everybody. I just feel so strongly at the moment, particularly the people who are not getting vaccinated and everything, just how selfish it is because so many people depend on this June 21 date, they really depend on it.

“I’d say to everybody, please support theatre and live music – it is the heartbeat of the country, what we do. It is essential. Support your theatres everywhere and get vaccinated.”

A number of shows in London’s West End are getting back under way after coronavirus restrictions were eased.

Musical Everybody’s Talking About Jamie, which was inspired by the 2011 television documentary Jamie: Drag Queen At 16, and follows a teenager who lives on a council estate in Sheffield as he overcomes prejudice to become a drag queen, will reopen on May 20, as will Amelie The Musical, based on the hit film.

Six The Musical and Magic Mike Live, created by Channing Tatum and inspired by the films in which he starred, will return on May 21.