Altman spent the weekend scouting sites in addition to the Fitzgerald Theater to film Keillor's unnamed comic fable about an iconic radio show that is suddenly canceled after 30 years on the air, the Minneapolis Star Tribune reported.
Filming had been set to begin last year, when script changes got in the way, and in January, when finances were an issue.
"I am preparing for the role by making it smaller and making other actors' roles bigger," Keillor said.
Keillor said he must lose 37 pounds by the start of filming in July.
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