A scheduling conflict has prevented Tony winner Mitchell from appearing in the role.
The artists will be backed by the Chicago Symphony Orchestra, which will be conducted by Paul Gemignani. Additional casting will be announced shortly.
LuPone's last musical theatre outing at Ravinia was Rose in Gypsy, a role she later repeated on Broadway to Tony-winnning effect. LuPone previously played the role of Oakley in a one-night-only benefit concert at Lincoln Center Theater's Vivian Beaumont. The upcoming concerts will celebrate the 150th birthday of Annie Oakley.
Cassidy eventually played Frank Butler in the most recent Broadway production of Annie Get Your Gun. His other Broadway credits include The Pirates of Penzance, Leader of the Pack, 42nd Street and Aida.
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