All hail the National Theatre's temporary space, for without it, the NT wouldn't be able to stage some of the stranger, but no less delightful plays. In Rufus Norris's first season as artistic director, he's decided to revive Tim Crouch's excellent 'An Oak Tree' where two people onstage, the playwright and an actor who has literally just turned up on the night, tell a story of loss and suggestion. Each night, it's a different actor, who doesn't get to see or read a word of the play until they are there onstage. The endlessly playful Crouch's recent 'Adler and Gibb' was a big talking point last year. This is one of his more intimate, older works (ten years old this year) and by all accounts a treat. In the past, the likes of Christopher Eccleston, Mike Myers, David Morrissey, Gina McKee and Sophie Okonedo have all stepped into the part.