Izzard will play Abbott Thrush, an upper-class English barrister brought in to fight Lockhart/Gardner in a libel case that finds its way into British court.
The actor is currently scheduled for one episode, but co-creators and executive producers Robert and Michelle King are leaving it open for a possible return.
"The Good Wife" stars Emmy Award winner Julianna Margulies ("ER," Festen) as a wife and mother who boldly assumes full responsibility for her family and re-enters the workforce after her husband's very public sex and political corruption scandal lands him in jail. According to CBS, "Pushing aside the betrayal and crushing public humiliation caused by her husband, Peter, Alicia Florrick starts over by pursuing her original career as a defense attorney."
Izzard was nominated for a Tony Award in 2003 for his performance in A Day in the Death of Joe Egg and has also been seen on Broadway in Race. His film credits include "Ocean's Twelve," "Ocean's Thirteen," "Across the Universe" and "Valkyrie."
"The Good Wife" will return to CBS Sept. 25 and air Sunday nights at 9 PM ET.