The five-time Emmy Award-winning actor, who was nominated for an Oscar this year for his role in "Into the Wild," will play Walter Perkins, a terminal cancer patient who impacts the life of Dr. Kovac and affects a major decision in his life, the network said.
The episode is scheduled to air April 24.
"The show has had an amazing array of incredible actors who have walked through the doors over the years and Hal Holbrook certainly continues that tradition. He is perfect for this role and we couldn't be more pleased to have him," executive producer David Zabel said in a statement.
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