It was a little like sitting at your grandfather's feet listening to him ramble on about his life.

But this grandfather was a traitor to his country, a former spy for the KGB, a former knight of the realm and adviser to the Queen on her art collection.

Set in 1979, this play tells the true-life tale of Anthony Blunt, a man who was unmasked in the House of Commons by Margaret Thatcher.

He was under siege, confronted by his principles and his life.

Corin Redgrave, of the Redgrave acting dynasty, played Blunt in a show which he had both scripted and researched.

It was a brief piece, lasting only an hour but, for that time, you couldn't help but be immersed in bitterness, reminiscence and the idea of a better life.

The show opened with a chorus version of the Internationale, which, for me, remains one of the world's greatest tunes of hope.

We first met Blunt in brown pyjamas and dressing robe as he awoke from a nightmare the day after his unmasking.

Redgrave quickly established the man. The snooty aesthete, the elitist art historian and scholar who once had the dream of a Bolshevik utopia and who was adamantly against the rise of Fascism.

His first recollection was of visiting his former nanny with spy colleague Guy Burgess, and becoming aware of the meanness of his parents.

Nanny was paid 15 shillings for a six-and-a-half-day week and given no pension when she retired.

Blunt determined to remedy this but she died before he could make the arrangements.

Redgrave as Blunt was revealing and he swiftly invited the audience into his life.

He was angry at his own betrayal by Queen and government - the monarch stripped him of his KCVO after the Government had promised immunity.

He produced flashes of anger alongside jokes at his own expense and he revealed how his Bolshevik principles were eventually betrayed by Stalin and his actions during the Spanish Civil War.

Redgrave was a mesmerising figure and painted a blinding portrait of a man finally having to come to terms with himself. If I have a quibble it is that, because of the tight running time, I wanted much more.