The forward drove the right side and carried the puck behind the Montreal net, doing a lap around the offensive zone before cutting across the front of the goal and shooting past Jake Allen.
"It's incredible," Kings goalie Cal Petersen said. "Tons of speed, for him to be able to control the puck and get across the net like that and make that, it's huge. And he's one of the guys that we count on in those overtime situations. He has plenty of game-winning goals like that so we count on him to do that, and he comes through."
Kempe has scored 11 game-winning goals in his NHL career, including three overtime goals.
Alex Iafallo scored to extend his point streak to seven games, and Petersen made 33 saves for Los Angeles (7-5-1), which won back-to-back games on the road for the first time since Feb. 4-5, 2019, against the New York Rangers and New Jersey Devils. The Kings defeated the Toronto Maple Leafs 5-1 on Monday.
"I thought we really picked some momentum up in that second period, couldn't find a way to score, Allen was tremendous," Kings coach Todd McLellan said. "And then we scored in the third, and after the power play, we didn't get a lot off that, we actually lost the momentum, they got some life and Cal had to make some good saves. So the good thing is we found enough to win on back-to-back nights."