The premise (if you've never seen Corden do one of these before) is that the players wait until the traffic light turns red, then dash out into the crosswalk and try to finish a number before the light turns green again. Motorists are alternately confused, delighted and infuriated.
At one point, after Corden is slow to leave the crosswalk and a motorist honks at him, he waves a chair at the driver. "Did you hear those car horns?" he asks his fellow performers once he reaches the safety of the sidewalk. "That's a standing ovation."
Efron's bleeped response: "What the f*** is going on?" He also weighed in, "This is not the best way to do a musical. Or cross the street."
They next did a song from "The Greatest Showman," with Corden dressed up as the Bearded Lady and with Efron unsuccessfully trying to ride a tricycle. Corden and Jackman nearly came to blows because the host wouldn't stop calling the "X-Men" star "Huge," but it all worked out in the end.