Keach was scheduled to play Ernest Hemingway in Jim McGrath's one-man play "Pamplona" at the Goodman Theatre in Chicago from May 30 to June 25, 2017. Keach appeared in previews of "Pamplona", May 19 through May 28, and was well-received by audiences. On opening night, he suffered a mild heart attack on stage and the next day, Keach had bypass surgery. On June 2, the Goodman Theatre announced that the entire run would be canceled after Keach's doctors advised a period of rest and recuperation.