Jimmy Cricket says the closure of the iconic Grand Theatre in Blackpool would be a “tragedy” for future generations.
The theatre, which was almost demolished in 1972, could be closed because of the effects of the coronavirus pandemic.
Management warned it would shut unless the government intervened.
Most of the 57 staff were furloughed during the lockdown.
They could be left redundant when the job-saving scheme ends on 31 October.
A charitable trust has run the theatre since 1972, when local campaigners saved it from the bulldozers.
Among them were entertainers such as Sir Ken Dodd and BBC broadcaster Alistair Cooke.
It reopened in March 1981 with a performance of The Merchant of Venice starring Timothy West and Prunella Scales.
Like other provincial theatres which depend largely on box office receipts to keep going, the venue has had no income since the lockdown began.
All tickets were refunded for cancelled shows and plays.
‘We must all get together‘
The theatre, which first opened in 1894, had applied for a £500,000 government grant to keep it going until it might be able to put shows on in January.
However, if social distancing measures were still in place then, it would not make the shows viable and also the money would have run out.
Jimmy said: “We must all get together to save the Grand in Blackpool folks.
“To deprive future generations of this wonderful theatre would be a tragedy.”
His post on Twitter attracted hundreds of likes and retweets as well as some comments.