Boris Johnson’s perceived lack of commitment to academia as a schoolboy was highlighted in a letter from Eton College read to a live audience at the Royal Albert Hall.

His one-time leadership rival Rory Stewart took to the stage at the sold-out London venue to read words penned by the Prime Minister’s former house master, Martin Hammond.

The former Tory politician was joined by a star-studded cast including Olivia Colman, Stephen Fry and Benedict Cumberbatch, who wowed the audience of the largest ever Letters Live event on Thursday evening.

The series, which started in 2013, sees performers bring to life letters from around the globe, recent and historic, in a “celebration of the enduring power of literary correspondence”.

Mr Stewart joked that letter constituted his resignation from the Conservative party before reading the part of the note, sent to the PM’s father Stanley Johnson in 1982.

The audience seemed to delight in the letter, which alleges the schoolboy had adopted a “disgracefully cavalier” attitude to his classical studies and “sometimes seems affronted when criticised”.

Away from the political, Colman gave a preview of what her royal touch will entail in the new series of The Crown as she read a letter from the Queen Mother describing the bombing of Buckingham Palace.

The award-winning actress, who will star as the Queen in the next season of the television series charting the monarch’s life, was welcomed on stage with cheers of delight and surprise.

Adopting an upper-class inflection, Colman read out the letter the Queen Mother wrote to her mother-in-law, Queen Mary, in 1940 during the Second World War.

After describing how they heard the scream of a bomb which then exploded in the palace quadrangle, the Queen Mother recalls walking through the damage of the city.

She wrote: “It does affect me seeing this terrible and senseless destruction – I think that really I mind it much more than being bombed myself.”

Colman drew laughter as she finished the letter by proclaiming “Dear old B.P. is still standing and that is the main thing”, and waved and blew kisses at the audience before leaving the stage.

Cumberbatch also had the auditorium howling with laughter in his account of a unnamed man who managed to get his genitalia stuck in a toilet paper holder and the disastrous – and very public – rescue that unfolded.

Fry struck a more reflective note as he read out a letter he had written to a fan who had asked him for advice on how to cope with depression.

In his reply, he tells her to not to blame herself and to consider her moods like the weather – something that cannot be controlled.

Jude Law also struck a sombre tone with a letter to the future from climate scientists, warning of the devastating reality of climate change.

As well as the fourteen readers, the show featured two music guests, with Damon Albarn and Sampha providing piano-led performances.

Cumberbatch, a co-producer of Letters Live, said: “It’s been remarkable to be part of the journey that Letters Live has been on these past six years – from such humble beginnings to this sold-out night at the historic Royal Albert Hall.

“We were so lucky tonight in the depth and breadth of talent who gave of their time and skill and it is wonderful to be raising much needed funds to the National Literacy Trust, a truly important literacy charity that is doing such crucial work to support reading and writing across the UK.”