Norway manager Stale Solbakken made 10 changes after two group victories, including resting Manchester City forward Haaland.
But into the narrative void stepped Dembele, who delivered the second-fastest men’s World Cup hat-trick ever with three goals of the purest quality. Dembele moves on to four goals in the tournament after also scoring in the 3-0 win over Iraq on Monday, and his display here will perhaps ease some of the pressure on captain Kylian Mbappe to always be France’s match-winner.
It was an emotionally charged day for Les Bleus, who had to play this match without coach Didier Deschamps after he returned to France to attend his mother’s burial.
France completely dominated the early stages and deservedly broke through in the seventh minute. Having won the ball in Norway’s half, Mbappe spread it wide right to Dembele in space. The Ballon d’Or winner squared up his marker and slammed home past Egil Selvik. It was 2-0 in the 20th minute when Dembele completed a lightning counter-attack by cutting off the right-hand side on to his wizardly left foot and whipped a curling shot into the far corner.
Norway struck back within 79 seconds, the French defence declining to respond to an attack straight from the kick-off which ended in Rangers attacker Thelo Aasgaard sweeping the ball past a wrong-footed Mike Maignan.
But Dembele was far from done, as he moved himself into contention as the tournament’s top scorer with his fourth goal when he again cut on to his left foot and, with four surrounding defenders, curled another effort past Norway reserve keeper Selvik.
Dembele was subbed off after 65 minutes as the tempo dropped after the break, but his Paris St-Germain team-mate Desire Doue stepped up to add a fourth in the 94th minute with a looping header.