Eoin Morgan matched his own record for the fastest half-century by an England batsman in a Twenty20 international as the tourists clinched a 2-1 series victory over South Africa after a SuperSport Park thriller.
Heinrich Klaasen blasted 66 from only 33 balls after Temba Bavuma (49 off 24) and Quinton de Kock (35 from 24) laid the platform for the Proteas, who posted an intimidating 222-6 at Centurion on Sunday.
England embraced the challenge of pulling off their second-highest successful run chase in the shortest format to turn the series around, Morgan making an astonishing 57 off 22 deliveries as they got home with five balls and five wickets to spare.
Captain Morgan struck seven sixes, equalling the England record of a 21-ball fifty that he set against New Zealand last year, after explosive knocks from Jos Buttler (57 from 29) and Jonny Bairstow (64 off 34).
There were 28 sixes in a contest which proved to be a batsman's paradise at altitude, with England ending a successful tour on a high note after also coming from behind to secure a 3-1 Test triumph and draw the ODI series.
De Kock capitalised on winning the toss by delivering a brutal onslaught along with Bavuma, the openers needing only 22 balls to get 50 on the board.
The captain disdainfully hammered Chris Jordan for three consecutive sixes, with Mark Wood also given the treatment before De Kock struck Ben Stokes (2-35) to Bairstow in the deep.
Bavuma drilled Adil Rashid's first ball over the rope, but the spinner got a measure of revenge when he bowled him one short of a half-century and Stokes struck again to see the back of Rassie van der Dussen.
Klaasen, in for JJ Smuts, then took centre stage, racing to a half-century in 25 balls, with 23 runs coming off an over from a struggling Wood.
David Miller made only nine in a fourth-wicket stand of 66 with Klaasen, whose scintillating knock was ended by Tom Curran (2-33), but his unbeaten 35 got South Africa up to their fifth-best T20 total.
In England's response, a fine catch from Tabraiz Shamsi sent Jason Roy on his way in Lungi Ngidi's second over before Buttler set about the returning Dale Steyn and took only 23 deliveries to reach his half-century.
Bairstow also looked ominous, dispatching Shamsi and Bjorn Fortuin into the crowd as the 100 mark came up inside nine overs, but Buttler gave it away when he was caught ramping Dwaine Pretorius.
The clean-striking Bairstow was bowled by Andile Phehlukwayo, having nailed three sixes, and England needed 78 from 38 when Dawid Malan - replacing the unwell Joe Denly - edged behind in a superb over from Shamsi.
Morgan middled Pretorius over the fence twice in the next over to silence the crowd and did the same to Ngidi after ending Steyn's spell with a six.
Stokes launched Phehlukwayo for back-to-back sixes before an incredible stand of 61 off 4.3 overs was ended when he holed out to Ngidi.
An imperious Morgan struck another two sixes in that same penultimate over from Ngidi, and Moeen Ali struck the winning runs after both he and the skipper offered chances to Pretorius.