In 2003, McCrystal directed an acclaimed production of Joe Orton's Loot at the Derby Playhouse.
In 2011, McCrystal was invited by Nicholas Hytner to work alongside him as Associate Director on the National Theatre's production of Richard Bean's One Man, Two Guvnors, a reworking of Carlo Goldoni's 18th century Commedia dell'arte play The Servant Of Two Masters.