Barbara Walters is disclosing a past affair with married U.S. Sen. Edward Brooke from Massachusetts.
Walters revealed details of her relationship three decades ago on "The Oprah Winfrey Show" scheduled to air Tuesday.
She remembers the moderate Republican as "exciting" and "brilliant."
Brooke took office in 1967, becoming the first African-American to be popularly elected to the Senate.
Walters said both he and she knew that public knowledge of their affair could have ruined their careers.
At the time, the twice-divorced Walters was a rising star in television news and co-host of NBC's "Today" show, but would soon jump to ABC News, where she has enjoyed unrivaled success.
Her affair with Brooke, which never before came to light, had ended before he lost his bid for a third term in 1978.
Brooke did not immediately return calls by The Associated Press Thursday.