“What’s my motivation?” It has become one of theatre’s most abiding clichés and it forms part of the plot of this acclaimed play by Jack Thorne and directed by Sam Mendes that is anything but clichéd. It’s a love letter to theatre certainly, and more thoughtful than comic, but a truly compelling work. It has already been lauded at the National Theatre, recently bagging Best Play gong at the Evening Standard Theatre Awards, and now transfers to the West End.