But this eviction is not quite what it seems – the flat turns out the be the former family home of Mr Avalon's 18-year-old stepson Curtis, who's keen the revisit the bittersweet memories of his youth and ends up learning something about the true nature of his stepfather in the process.
As in so much of his work, Ridley shows himself concerned with the nature of human relationships in dangerous, run-down environments, and explores the redemptive power of storytelling.
Curtis (played with touching innocence by Sean Verey) is a flawed hero, a young man who has blindly spouted the hateful rhetoric of his powerful family and turned his back on the good people around him, particularly ex-girlfriend Sarah (Emily Plumtree).
On arriving at the flat, he finds himself forced to confront the ghost of his dead brother – who he has been told died while travelling – as well as the people Mr Avalon wishes to remove; immigrants, disabled people and homosexuals.
Ridley fires a powerful broadside against the hypocrisies of the far-right – an important thing to be reminded of as we approach an election (our news story on the production attracted no shortage of unsavoury comments from BNP supporters). The Moonfleece of the title is a sharply conceived metaphor for all that we value in a liberal society.
This timely revival (the play's professional premiere) is skilfully directed by David Mercatali, and performed by a cast of newcomers showing great promise – including Reece Noi, David Ames and Sian Robins-Grace.