The 39-year-old resurfaced recently at some event, looking serious.
Michael left "Blossom" to write on "Late Night with Conan O'Brien," a move which he reportedly regrets.
Stoyanov played one of the Joker's henchmen in the 2008 film "The Dark Knight."
4/12/2010 4:10 AM PDT BY TMZ STAFF
Get TMZ Breaking News alerts to your inbox