In the past several years Mahoney had been very active in the Chicago theatre community not only with Steppenwolf but with Northlight Theatre. I had seen him in at least 8 productions in the past several seasons including his last role as the dying gay lover in The Rembrandt. Steppenwolf has cancelled performances tonight and I assume both New York and Chicago theatres will dim their lights in his honor in the next week.
This hurt...what's even more impressive is he didn't start acting until his 30's didn't have much training to speak of. You couldn't teach what he had. Funny as hell, stupid good as what he did. He'll be missed for sure.