Warning: this article contains spoilers to Fleabag.

That’s it. The End. Or at least, according to Sian Clifford, who plays Fleabag’s sister Claire in the show that has become a breakout hit in the UK and US: “It is complete.”

Series two, which has just wrapped up, marks the end of the sitcom about a Londoner grappling with the death of her best friend, a troublesome family, running her own business and navigating a tangle of unfulfilling and masochistic relationships. In truth, Fleabag waving goodbye to the camera should have been all we needed to know that this was the last we’d see of Phoebe Waller-Bridge’s character – whose actual name we never learned. But who thought one of the final shots would be of a CGI fox?

The first series of Fleabag won critical acclaim and was praised by fans for its emotional and sexual honesty, and for characters who were not always likable, never mind loveable, but also often very relatable. Series two raised the bar so utterly that, at times, Waller-Bridge’s risks and progression were so impressive all one could do was shake one’s head in appreciation. (And, in the case of episode three, watch it again immediately afterwards.)

Perhaps we should never have even considered that Waller-Bridge would fall to the sophomore slump, given she is winning rave reviews off-Broadway for the one-person origin show of Fleabag, which debuted in Edinburgh in 2013.

A couple of things in particular made series two so special. First: the astonishing development that saw breaking-the-fourth-wall itself broken. A meta break, if you will. I can’t remember ever seeing this as a device, and the moment it came (“Where did you just go?”) was the most unexpected television twist in recent years.

Second: the staggering performances of the new cast additions. Andrew Scott, as the Priest (we never learn his name, either) was unbelievably good, as were Kristin Scott Thomas and Fiona Shaw in cameos; and Sian Clifford, in particular, delivered a knockout performance as Claire. In series one she was the uptight sister, but the focus was very clearly on Fleabag’s travails. In series two, that uptightness was fully explored with a layered, nuanced performance that took in Claire’s insecurities and the ways in which she distracts from her truly awful husband, Martin (the brilliantly slimy Brett Gelman, who, in full credit to his performance, I’d frankly be happy never to set eyes on again).

The opening episode of this series has been called genius, but it was the third that really stood out. How Waller-Bridge can pack so much into 23 minutes is extraordinary. The farce of Fleabag dropping and shattering the glass trophy “worth thousands” mere seconds after Claire instructs her: “Don’t play with that.” The mad dash past London landmarks to the sounds of Moscow Symphony Orchestra. The typically quirky lines: “Oh, I love courgettes. You can treat them appallingly and they still grow!” The perfectly-pitched awkward social comedy of the flirting between Claire and … Klare. Claire’s explosion of anger: “You just make me feel like I’ve failed.”

Episode three also featured the two most talked about moments of television in years. The aforementioned bit when the Priest notices Fleabag’s asides, and the five-minute monologue from Scott Thomas on women’s pain. Searingly accurate, hilarious and probably dissected for years to come: “Women are born with pain built in … period pain, sore boobs, childbirth.

Searingly accurate ... Kristin Scott Thomas’ monologue as Belinda will resonate for years to come. Photograph: Luke Varley/BBC/Two Brothers

“[Men] have to seek it out … then they create wars, so they can feel things and touch each other, and when there aren’t any wars, they can play rugby.”

The other scene that set social media ablaze was the Priest’s instruction, in episode four, to Fleabag: “Kneel.” Which reduced, well, everyone to crumbling lust.

The exploration of grief also won plaudits. One episode was given over to the death of Fleabag and Claire’s mother, a subject purposely almost entirely avoided until that point. Waller-Bridge nailed the contradictions and complexities of grief. The often absurd and incongruous elements of funerals and wakes. The unexpected emotions that creep in: the humour in Fleabag looking gorgeous at the funeral; the inclusion of what I call a “grief thief” – Fleabag’s then-boyfriend, exaggerating his connection to the deceased – the uncomfortable, stymied conversation with her father.

If there were things that didn’t quite hit home, there were few. Given that Waller-Bridge’s guilt over the death of her best friend, Boo, has been such a pivotal theme through both series, there was an odd lack of explicit resolution. I’d also forgotten Hugh Dennis’s bank manager – who we met in series one (in one episode giving a quietly affecting speech, to be fair) – so his brief reintroduction, without a reminder of who he was, was discombobulating. I felt I was making eye contact with someone on a bus who I couldn’t quite place.

There has been some criticism that Waller-Bridge’s poshness – and Fleabag’s relative poshness – is a barrier to entry. But it just doesn’t stack up that a character who admits life would be so much easier if someone could just tell her what to do is not identifiable. Series two was also more representative relative to race and sexuality.

It is typical of Waller-Bridge’s talent that she managed to wrap things up while staying true to her habit of side-stepping our expectations. That audience-cheering moment where Claire finally rids herself of Martin: but for a second, during his speech, there was what seemed a flicker of contrition and the worry Claire wouldn’t hold firm. (Also, a nice detail that she wanted him to leave her – and another moment of kneeling.)

Subverting the rushing-to-the-airport trope ... Fleabag and Claire. Photograph: Luke Varley/BBC/Two Brothers

The subversion of the rushing-to-the-airport trope was great. (I particularly enjoyed the nod that Claire had already stalked Klare’s flight number and time.)

We also had a sort of amnesty between Fleabag and Olivia Colman’s insufferable soon-to-be stepmother, and yet, entirely in-keeping with character and with Waller-Bridge’s writing, Colman’s character (also never named) couldn’t help a last-minute barb. We also got a heart-to-heart between father and daughter – though it took a trapped foot to make it happen.

As for that ending: the Priest’s speech on the nature of love was electrifying. “Love is awful. It’s painful. Frightening. It makes you doubt yourself, judge yourself, distance yourself from the other people in your life. Makes you selfish, makes you creepy, makes you obsessed with your hair.” Who among us could not relate? “It takes strength to know what’s right. And love isn’t something that weak people do. Being a romantic takes a hell of a lot of hope.”

The man who reduced everyone to crumbling lust ... Andrew Scott as the Priest. Photograph: Luke Varley/BBC/Two Brothers

There will be many people disappointed that Fleabag didn’t get her happy ending, because the Priest chose God. But she did, of course, in the way that she has grown. In the cafe thriving; in the relationships she has repaired; in the shift from having meaningless sex to allowing herself to be loved. We do not get the feeling that Fleabag’s next move after walking away from the bus stop would be to go and get trashed and bed some slimeball from a bar, which would have been the reaction of series one Fleabag. (Which, given that she has just lost the man she loves, probably would have been entirely justified.)

Romantics (hi) might be disappointed by this parting of ways, but that is offset by the fact we know Fleabag will be OK. That the Priest, who truly saw her (as did Fiona Shaw’s therapist), called her out on her coping mechanisms and deflections and helped her overcome them.

Finally, the series once again excelled in its artistic choices – from the final choice of the Alabama Shakes track This Feeling (almost certain to be rising to the top of Spotify streams) to its general soundtrack composed by Waller-Bridge’s sister, Isobel, and also in fashion, as my colleague Jess Cartner-Morley brilliantly wrote about. The direction and art design and art direction were even better than in the first series.

Judging by social media chatter and IRL conversation, it seems as though many who either did not watch the first series, or who didn’t think it lived up to the hype, have been converted by the second. The writing; the performances; the verisimilitude. Fleabag will be a tough act for Waller-Bridge to follow.

• This article was amended on 9 April 2019 to correct a reference to Fleabag’s age.