The Split season 3 review: final series of Nicola Walker divorce drama is all about endings, good and bad

The third and final series of The Split is all about endings. It begins in the wake of Hannah (Nicola Walker) and Nathan Stern’s (Stephen Mangan) separation at the end of last series, the two divorce lawyers now having to negotiate their own separation – the natural, if not necessarily inevitable, conclusion to a series that’s often wondered aloud if there’s such a thing as an amicable split. What quickly becomes apparent is that neither are quite sure of where they stand with the other, or even always where they stand with themselves.

Walker and Mangan are great in the scenes they share together, embodying a sort of comfortable but strained chemistry – easy laughter giving way to awkward pauses as twenty years of familiarity between Hannah and Nathan is distorted by a very new dynamic. Each time they interact, there’s this cautious façade papering over deeper regrets and fears and selfish instincts, both of them holding back what they really want to say (until, of course, they don’t). Some of the best scenes of previous The Split’s previous series have been those shared by Hannah and Nathan (always more interesting than blank-slate Christie), which proves true again here.

Things are complicated between them by Kate (Lara Pulver), Nathan’s new girlfriend of a few months, introduced suddenly and unexpectedly to Hannah at the beginning of the episode. She’s a child psychologist with a new book out – about the impact of divorce on families – which she’s quick to mention at any opportunity. Kate’s sanctimonious in a serene sort of way, exactly the sort of person who would irritate Hannah most, and probably the audience too. Pulver commits wholeheartedly, though the character is maybe pitched a little too overtly dislikeable – too obviously an obstacle for Hannah and Nathan, when it might’ve been more complicated if she was that little bit more sympathetic.

What’s striking about The Split’s third season is that it’s not just about endings, but deaths too. A number of the legal procedural cases are about death: Lindsay Duncan is having a ball in her guest appearance as a particularly acidic Duchess, disputing the new ownership of her ex-husbands’ estate, and another client separates from her husband after a terminal diagnosis. There’s something almost funereal hanging over the series it closes, which casts a pall over different subplots – what’s the secret Prof Ronnie (Ian McElhinney) is keeping? – and adds to that sense of the series winding down.

Executive producer Abi Morgan (who also makes her directorial debut this series) explained that she wrote the series after “some big life changes,” and you can see how those might’ve played on her mind during the scripting process. “There have been various family illnesses and I also went through cancer just before we went into lockdown,” Morgan explained to the BBC, which likely accounts for some of those themes that recur through The Split, with the series now asking not “what if we have children?” but instead “what if one of us doesn’t survive?”

It’s a clever thematic angle for the series, which leaves the drama feeling heightened and more significant – more mature in a way, too, offering the kind of stories you can only tell after spending a few years with characters and becoming more familiar with them over time. Almost immediately, the new series feels like The Split’s best – and certainly Nicola Walker’s best performance in what’s probably the role that’s offered her the most opportunity to show her skill. It’ll be missed when it ends.

The Split Series 3 begins on BBC One at 9pm on Monday 4 April, with new episodes airing weekly and the full series available as a boxset on BBC iPlayer. I’ve seen the first two episodes of an eventual six before writing this review.