They made the playoffs thrice in the first five seasons. In the first two of them, they had Shikhar Dhawan in their roster. He was released, as were many others, players who have since gone on to hurt Delhi - then Daredevils, now Capitals - along the IPL journey. Now, under a new management and very different personnel in the ranks, they returned with smart buys at the auction, giving new leader Shreyas Iyer an opportunity to carve a niche. And Dhawan back where he began. And they have broken a six-year itch.
For an idea of the scale of the turnaround, since 2012 - when they were last in the playoffs - they have never finished above sixth place, taking the wooden spoon thrice in six seasons along the way
Dhawan continues stunning resurgence
Dhawan has been a consistent performer in the IPL - six times he has crossed the 400-run mark in a career where he has represented multiple teams, returning to Delhi with Capitals this season after turning out for Daredevils, Mumbai Indians, the now-defunct Deccan Chargers and Sunrisers Hyderabad over the years.
Even by those high standards, he's having arguably his best season as an IPL opener this time: his strike rate of 137 is currently his highest ever.
On Sunday, Dhawan cracked another fifty, his fourth in the last six games, to keep alive the purple patch and recover from a poor start to the season. So well has he gone that Dhawan has surpassed the likes of Chris Gayle and David Warner in this period, topping the Powerplay strike-rates chart at 173 runs per 100 balls.
Dhawan's run has coincided with a run of form that has seen Capitals win five of their last six games, despite opening partner Prithvi Shaw struggling to find his range after an epic debut season in 2018.
Late surge makes the difference for Capitals
The pitches at Feroz Shah Kotla have been tricky ones, some of them have come into a fair bit of criticism too. On Sunday, however, it was a good one to score runs on, at least at the start and, thanks to some poor death-overs bowling, at the end too.
Capitals put up the biggest total of the season at the ground, their 187 for 5 marginally higher than the 185 both Capitals and Kolkata Knight Riders put up back on April 12. Could it have been more, even 200-plus? Perhaps.
At the toss, Capitals captain Iyer opted to bat and explained that he was "assuming it will play well in the first half". It did, and Shikhar Dhawan and Iyer put together 68 runs for the second wicket, both batsmen going on to score half-centuries.
But, after Capitals had reached 102 by the end of the 12th over, they added just 12 runs in the next two. Capitals started the 17th over with just 141 on the board. It took some big hitting from Sherfane Rutherford and Axar Patel to take them to 187, perhaps slightly lower than where they could have been.
Another chart-topper Royal Challengers could have done without
Still, the finish was spectacular. Rutherford and Colin Ingram in the middle and there were only three overs left. Navdeep Saini had the ball. He went for 10 runs, even if he saw the back of Ingram, and the next three overs were smacked around for 10, 16 and 20 as Rutherford and Axar got stuck into the bowling.
Capitals added 56 runs in the final four - death - overs, and the last three had all of the don't-bowl lengths: full toss outside off - check. Short on leg - check. Full outside off - check. The last ball, an attempted yorker that became a full toss outside off, was dispatched for a one-handed six over backward point by Rutherford.
The Powerplay star
Off-hand, what would your picks be if we asked you: who are the quickest-scoring batsmen in the Powerplay in IPL 2019?
Will Parthiv Patel make your list? Unlikely, but he should.
Here, look at the batsmen with the best strike rates in the Powerplay this season...
There are many things Royal Challengers haven't done right this season - sticking with Parthiv at the top of the order is one they have.
With inputs from Gaurav Sundararaman and Shamya Dasgupta
Srinath Sripath is a sub-editor at ESPNcricinfo