The Diplomat becomes the show it was always meant to be in season 3

*Warning - Contains major spoilers for The Diplomat season 3 episodes 1-3*

It's no secret that some series take time to bed in. How many times have we all heard, "Oh, you should really watch this show – you just have to get through the first season or two, then it gets good"?

It's the complaint which has so often been levelled at Netflix – that it doesn't give its original shows enough time to establish themselves and find their feet, before swinging the axe of cancellation.

Sometimes there's a reason why a show may fumble at first. For instance, there's The Office US, which relied too heavily on its British predecessor's formula before feeling the confidence to go out and find its own identity.

Then, there are simply those playing the long game, establishing their story to a necessary degree and working through the less interesting backstory before they can finally arrive at what feels like a perfect destination and groove, one which they can exist in for a long time to come.

It turns out that fitting that pattern perfectly is The Diplomat – and now, in its third season, its time has come.

Some viewers have been with The Diplomat since its beginning, instantly falling in love with its soapy melodrama-style look at politics. I was not one of them.

Where season 1 was somehow both overblown and also a bit dull, season 2 settled out a bit, becoming funnier and amping up the twists to great effect.

Now comes season 3 and I'm delighted to say it's a triumph. It's not the series I was hoping it would be ahead of season 1, but instead it has established itself as something that feels both a natural progression of what came before, and also something entirely new – and it's all because of one twist.

No, I'm not talking about the dramatic cliffhanger at the end of season 2, which played perfectly into the show's almost trademark blend of silliness and stakes – the president died of shock while speaking with Hal on the phone.

Instead, I'm talking about the twist that comes at the end of the season 3 premiere, where the new president, Grace Penn, picks Hal Wyler to be her vice president, rather than the choice who has been lined up for seasons now, his wife Kate.

It's the sort of twist that not only knocks your socks off, coming as a genuine surprise, but also once the dust has settled, just feels right.

Not right for the world of the show, of course – Hal is slippery, conniving and utterly self-centred, while Kate has genuine diplomatic nous and skills which could be put to supremely effective use in the role. However, it is right for the series itself, which almost instantly becomes a new show at its most basic essence.

If you were to describe The Diplomat to someone ahead of season 3, you would say that it's a political drama about the American ambassador to the UK. You may just about throw in that it also touches on her rocky marriage, but that might be a stretch for the purest of pub talk.

If you're a political obsessive like me, that may sound interesting, but the execution was so lacking in realism and detail that the show failed to match up with that target audience.

However, if you were to describe the series after season 3, you would say it's about the American ambassador to the UK trying to stop crises while also battling with her husband, the vice president, as their marriage crumbles. Now that sounds like a good show, regardless of political geekery.

And it is. It's a formula which perfectly suits the show's set-up as a real blend of the personal and political. The relationship dynamic between Kate and Hal was always the best part of the show, but now it has a real tie to the ongoing political storyline and real, meaty stakes. If this wasn't always creator Debora Cahn's plan, it certainly feels that way.

The more explicit fracturing of the marriage that we see in the first few episodes of season 3 also frees Kate up for romantic storylines that aren't quite as languorous and drawn out as the one she's had with Austin.

While that is certainly continuing this time around under the surface, anyone who's watched the trailer for season 3 will know it also sees Kate having a dalliance with Aidan Turner's new character, Callum.

It throws another spanner in the works when it comes to continuing both international and highly personal diplomacy, and also allows the show to indulge in the more steamy aspects it so loves in a way we genuinely care about.

Unsurprisingly, this season also benefits from a much bigger dose of Allison Janney, who becomes more of a fixture in the show's central cast.

Where Michael McKean's Rayburn was always a side character, popping up for occasional, fairly inconsequential scenes, Grace's role is crucial, and allows us a closer look at the corridors of American power.

It also helps that the character is so flawed from the off – no matter her explanations, we all know what she did with regards to the HMS Courageous, so we never feel like we're watching a one-note 'president' character.

Instead, we're watching someone willing to do whatever it takes to get the results she wants, and who is at all times fighting for her political life and personal freedom, were her big secret to ever get out.

Bradley Whitford's also a great addition to the cast – if we're honest, he doesn't have a whole lot to do this season, but he's such a charming screen presence, and his chemistry with Janney so well-established, that any scenes with him are still worth looking forward to.

It's also impressive that the series manages to keep Kate as such an engaging character and focal point, now that three of her supporting characters are the president, the vice president and the prime minister.

Oh yes, Rory Kinnear is still knocking about, still doing exceptional work and somehow managing to be both frustratingly unpredictable and yet also extremely easy to read. If you've ever felt that about a real-life politician – and quite frankly, it's hard not to see parallels – then he captures it perfectly, even if his screen time is more limited this season.

All of this, plus the show's visual splendour and high production value, all add up to a riveting third season, with twists and turns galore, personal drama we can really engage in and political machinations that are thrilling to behold.

Sure, it's not perfect – I have to admit that I've never been particularly engaged by the ongoing storylines of either Ali Ahn's Eidra or Ato Essandoh's Stuart, even if the latter does get a slightly more complex arc this time around.

But the key shift here has no doubt been in the dynamic between Kate and Hal, given a turbo boost by his ascension, her choice to remain as ambassador and their subsequent marital woes.

As the seasons have gone on, Keri Russell and Rufus Sewell have grown with their roles. Having started from a high standpoint as the selling point for the whole series, they are really excelling beyond anything we have yet seen here, and some of their sparring matches are magnificent.

The truth is, if you weren't on board with The Diplomat as it was, and gave up early in season 1, it's going to be hard to convince you to return and watch the full back catalogue, just to reach an optimal version of the show in season 3.

However, if you've stuck it out from the beginning, either because you've been a big fan from the start or you've been more mixed but wanted to see where it goes, then you're about to be blown away by season 3.

It would never have worked nearly as well were the hards yards not done by seasons 1 and 2, so I will accept that they had to exist to get us here. However, The Diplomat feels as though it is finally the series it was always meant to be – and I, for one, will be genuinely excited to see what Cahn and her team have cooked up for season 4.

The Diplomat season 3 is available to stream now on Netflix. Seasons 1-2 are also available – sign up from £5.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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