Dame Judi Dench has lent her support to a campaign to transform Reading Prison into a cultural and artistic centre.
The Oscar-winning actress said it was "vitally important" the site was used in a way that "pays tribute to its artistic history".
It comes after the sale to a developer of the Grade II listed prison, where Oscar Wilde was held, fell through.
Reading Borough Council is hoping to revive its bid to purchase the site and transform it into an arts complex.
In November, the Ministry of Justice (MoJ) said Artisan Real Estate had withdrawn from its purchase of the jail.
Describing the prison as a place of "such culture", Dame Judi said it would be a "great gift" to Reading, the UK and the world if it became a cultural hub..
"The idea of plays being performed, people learning and enjoying themselves, and a community coming together in a space that represented so much sadness and inspiration for Oscar Wilde himself is a beautiful one," she added.
Dame Judi is the latest actor to throw their weight behind the campaign.
In March, Stephen Fry, who portrayed Irish playwright Oscar Wilde in the 1997 film Wilde, previously said if "living art can rise up from the place where Oscar and so many others suffered, then how perfect that will be, for Reading, for Britain".
Toby Davies, artistic director of Reading-based Rabble Theatre, said he was delighted by Dame Judi's support, adding: "Reading has the opportunity to transform itself into an international cultural powerhouse and Dame Judi recognises that."
Reading East MP Matt Rodda said he hoped the MoJ would listen to the "growing calls for it to change its approach and save the gaol so that it can be used for arts and heritage".