What began as a nervy, chaotic opening quickly turned into an almost exhibition of control, timing and devastating finishing.
Van Veen struck first, edging a wild opening set that featured missed doubles, big finishes and a dramatic exchange at the business end. It would prove to be his only foothold in the match.
From the second set onwards, Littler shifted through the gears and never looked back.
The tone was set when he reeled in a spectacular 170 checkout to snatch the third set, treble 20, treble 20, bull, a moment that visibly drained belief from the Dutchman.
World Darts Championship as it happened: Littler thrashes Van Veen to retain title
Littler's scoring surged, his pace quickened, and his command of key moments became absolute.
Van Veen continued to play at a high level, producing ton-plus finishes, back-to-back maximums and even threatening nine-darters, but every rally was met with a response.
Littler punishes
Littler repeatedly absorbed pressure, waited for errors and punished them without mercy. Sets four, five and six passed in a blur of heavy scoring, clean set-ups and calm execution, including multiple 180s and a run of eight straight legs that broke the contest open.
Distractions came and went, including the now-infamous Ally Pally wasp and a mid-match board change, but nothing disturbed Littler's rhythm. Even when he missed opportunities, he returned with authority, correcting calmly and finishing decisively.
His ability to reset and close legs under pressure stood in stark contrast to Van Veen's growing frustration.
The end was emphatic. Littler built the finish, left himself 147, and took it out cleanly, treble 20, treble 19, double 15, to seal a 7-1 victory that felt both brutal and historic.
'I want to dominate'
"I was expecting Gian to throw the kitchen sink at me," Littler told his press conference.
"Obviously, he'd done that in the first set, could have gone 2-0 up, but from there, yeah, I don't really know what happened. He missed a few doubles here and there, and I just had to pounce on him.
"Nothing will ever beat a first world title for anyone in any sport, but this was just all about retaining it, bringing it back home with me for 11, 12 months. My name is on the list of world champions to go back-to-back. It's a very short list, but I'm on it.
"We focus on what's next. It's Bahrain and then over to Saudi Arabia. The other majors later on in the year, I'll be hunting them down.
"I want to dominate everything, and obviously, I want to try and win everything. The Masters, the Europeans, they're the two that I really want to go for.
"Me and mum and dad, we've put everything in it. This is why I'm here now. But it doesn't stop. We're on this roller coaster, and we've been on it for nearly three years now. I just keep going. Hopefully, keep winning as well."
'I took my chances'
"It feels amazing," Littler told Sky Sports immediately after clinching the world title for a second time.
"First of all, thanks to John McDonald and John Noble - what a fantastic career they have had. In my first year, Russ Bray retired; now these two legends! I'm a bit late to the party!
"I've been wanting to say this. Everyone knows what happened with Anthony Joshua and his guy and his team and his friends.
"Just like AJ said: the first time was so nice, I had to do it twice!"
"I started playing better from the second set. The first set, I wasn't happy going into the break, but I had to kick on from there.
"I said to myself, 'give it time, you will find it'. I started off from the left of the oche and moved over to the right. It all came to plan.
"Gian, what a tournament, he can be very happy. Every set he was there and behind me. I had to take my chances."
"This win has increased that gap from Luke Humphries and I'm in the clear for No 1."
Van Veen 'proud but disappointed'
"He's a fantastic player, which is why he's world number one by a margin now," admitted Van Veen on stage after defeat.
"That's why he's back-to-back world champion.
"I would have liked to pick up the title, but I would have liked to give Luke a game, and that's what I didn't do. I lost too many legs, and I missed too many chances. Looking back at this tournament, I'm very proud to have got to the final. Number three in the world and Dutch number one.
"I'm very proud of this achievement, but also disappointed."
Astonishing numbers
Littler averaged comfortably over a ton, converted his doubles at a ruthless rate and fired in a torrent of maximums. Both players sank an astonishing four ton-plus finishes.
More telling was his composure. He dictated tempo, chose moments to strike, and closed whenever the match threatened to breathe.
Littler averaged just shy of 104 for the entire tournament - the sixth highest in history. He also picks up the Ballon Dart - the award for most tournament 180s - after hitting 73 maximums. His nearest competitor was Gary Anderson, who landed 59.
A total of 1127 were thrown in the competition - unsurprisingly, a new record.
For Gian van Veen, the defeat will sting like a London wasp, but reaching the final caps a breakthrough year that has already reshaped the new number three's standing in the sport.
At just 18, Littler becomes the first player since Gary Anderson to successfully defend a world title, and does so with an authority that suggests there will be plenty more to come.
On this night, though, the stage belonged to Littler alone, who becomes only the fourth ever back-to-back world champion.