Transcript for 'Jeopardy' James returns to popular trivia TV game show
Finally tonight here, America strong. "Jeopardy!" James is back and so is the librarian named Emma who beat him. "Jeopardy!" James made his mark earlier this year. Unless you've been living under a rock for the past two weeks, you know about our current champion, James. Reporter: 35-year-old professional sports gambler from Vegas, a 32-game streak, winning $2.4 million. James? What is oxidized? Yes. What is C.S. Lewis? Yes. Reporter: And his Vegas skill. All-in. The house limit, please. Reporter: Even the buzzer, he practiced. How do you get so good at the buzzer? Try not to have any extra motion when you are pressing. Try to look at the single lights around the board that tell you when you can buzz in. Reporter: But "Jeopardy!" James would meet his match in 27-year-old Emma Boettcher, who actually auditions for "Jeopardy!" Four times before being picked. So, Emma, it's up to you. Reporter: And she won, doing what James often did. She went all-in. And tonight, "Jeopardy!" James Emma back later in the week. If they both win, they could face each other. I'm ready to win. Ready to win the tournament of champions. Reporter: James and Emma, all-in, all over again. We'll see. We can't wait. Good night.
This transcript has been automatically generated and may not be 100% accurate.