An Oak Tree, National Theatre
The play I have just seen is not the play you will see. Of course, one of the draws of live performance is that no two nights are the same, but that idea is taken to a mesmerising extreme in Tim Crouch's An Oak Tree, celebrating its 10th anniversary. Every night, a new guest actor " who has never seen the show nor read the script " joins Crouch in this two-hander; past playmates include Sophie Okonedo, Christopher Ec…