ST. LOUIS — So much for the contrite Donald Trump.

Running mate Mike Pence and other senior Republicans had warned the GOP presidential nominee he had to show regret and humility in the aftermath of a bombshell video that depicted him boasting about his sexually predatory behavior toward women.

Spoiler alert: He didn’t take their advice. And what followed Sunday night was the most bizarre presidential debate of the television age.

The combative spectacle was launched even before the second debate with Democrat Hillary Clinton began. Trump convened a photo-op, streamed live on his Facebook page, featuring four women who have accused former president Bill Clinton of sexual misconduct in cases dating as far back as his days as Arkansas governor.

During the debate, Trump labeled Clinton the worst abuser in the history of politics after dismissing the degrading language in his video as “locker-room talk” and nothing more.

“It’s just words, folks; it’s just words,” he said. “I apologized to my family; I apologized to the American people.”

For her part, Clinton was measured and cutting.

“With prior Republican nominees for president, I disagreed with them on politics, policies, principles,” she said in her first comments on the tape since it was released Friday. “But I never questioned their fitness to serve. Donald Trump is different.” She called him “not fit to be president and commander in chief.”

She called him a misogynist. He called her a liar.

If elected, Trump said he would instruct his attorney general to appoint a special prosecutor to investigate Clinton’s use of a private email server while she was secretary of State.