Bassett, who has starred in the films "How Stella Got Her Groove Back," "Malcolm X" and "What's Love to Do With It," will play a "tough-as-nails attending physician who is coming back to Chicago after doing tsunami relief work in Indonesia," the network said.
"Angela is a wonderfully talented actress who I've long hoped to work with," executive producer John Wells said in a statement. "We couldn't be more delighted that she's agreed to join us."
NBC renewed "ER" for a 15th and final season earlier this month.
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