Dopo essersi diplomato al Ridley College, Cronyn studiò drammaturgia alla McGill University, e continuò i suoi studi di recitazione alla scuola di Max Reinhardt e alla American Academy of Dramatic Arts. ###>==Career==Subsequent to graduating from Ridley College, Cronyn switched majors, from pre-law to drama, while attending McGill University, and continued his acting studies thereafter, under Max Reinhardt and at the American Academy of Dramatic Arts.