The Korea Republic forward paid the price pre-match for his underwhelming form this season as he was benched by Antonio Conte for his side's final game before the international break.
But last season's Golden Boot winner came off the bench after the break to steal the show in a remarkable performance that saw him net three goals inside a quarter-hour of play.
All three goals came with a degree of class, to ensure Spurs head into the international window on a winning note and leave Leicester boss Brendan Rodgers under increasing pressure.
The Foxes got off to a bright start when Youri Tielemans put them ahead from the penalty spot after just six minutes, but Harry Kane added another goal to his tally when he levelled for Spurs two minutes later.
Eric Dier have the home side the lead after 21 minutes, but James Maddison levelled for Leicester to send the sides in level at the break.
Rodrigo Betancour again regained the lead for Spurs shortly after the restart before Son's antics followed, his goals coming in the 73rd, 84th and 85th minutes.