“The last time he sang at Roy Thomson Hall turned out to be the worst night of Ben Heppner’s astonishing career. As they stumbled out of the hall into the cold night air in January, 2002, his hometown fans murmured that he might be finished. And for several agonizing months Heppner — one of the world’s greatest dramatic opera tenors — wondered whether they might be right. But Heppner is full of confidence and enthusiasm as he prepares for his Thomson Hall return tomorrow night, his first since that traumatic occasion.”