Counterpart: this cerebral, rip-roaring spy-fi series forces us to look in the mirror

This isn’t a spoiler, but the series finale for US espionage drama Counterpart is called Better Angels, a nod to something the high-concept show has been asking all along: is there a best version of ourselves?

Across the two seasons of Justin Marks’s series (which ran from 2017-2019), Counterpart explores questions about who we are and how we became that person. Not just as individuals shaped by tiny decisions, but also as a people, where whole worlds change because someone turned left instead of right. It’s nature versus nurture.

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And when those heady ideas are litigated through twisty and moreish plotlines teeming with secrets and double-crosses, it’s like hiding a dose of philosophy inside four scoops of chocolate ice-cream.

With stylish production design and first-class performances from Oscar-winner JK Simmons and the incomparable Olivia Williams (The Crown), Counterpart starts with an interesting hook. In the 80s, a science experiment in a Berlin lab produced an unexpected result: it created a mirror world to our own only accessible through a secret crossing inside a government building and overseen by a bureaucracy of mysterious “management”.

This parallel universe, dubbed the Prime world, began as a carbon copy of the original – the Alpha world. But life and living soon created divergences, and minute changes ballooned into vast rifts between the two realms.

Howard Silk (Simmons) exemplifies those rifts. In the Alpha world, he is a meek apparatchik, a low-level pencil-pusher with aspirations of a better job and no confidence to pursue them. In the Prime world, he has the life he thinks he wants – a hardened spy with a utilitarian streak.

Simmons creates two distinct characters with different gestures, mannerisms and worldviews, but enough similarities so you recognise that both Howards stem from the same root. It’s what happened to them that’s shaped them.

That goes for the other inhabitants of the Alpha and Prime worlds too – a clever tale of haves and have-nots. While the Alpha world lives in comfort, the Prime residents bear the battle scars of a global pandemic that killed millions in their realm. In the tragedy’s wake is a sea of lingering trauma, including a resentment that fuels certain Prime parties to strike back against those it deems responsible for their suffering: the Alphas.

A terrorist cell has embedded Prime “others” into the seemingly more prosperous Alpha universe, plotting to wreak vengeance. But it’s more than just heroes and villains: in the classic espionage tradition of authors such as John le Carré, Counterpart understands there are micro-shades in its shades of grey.

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Each character grows across 20 episodes of tension and mystery. There’s Emily Burton Silk (Williams), counterintelligence officer and Howard’s wife; Clare Quayle (Nazanin Boniadi), a sleeper agent with a long-term mission; Peter Quayle (Harry Lloyd), a manipulated husband with a well-positioned government job; and Nadia (Sara Serraiocco), an efficient and sad-eyed assassin. No one ends up where they started, and that’s Counterpart’s point – we’re all changed by what happens to us.

With Norwegian film-maker Morten Tyldum (The Imitation Game) as its pilot director, the show’s moody tone and kineticism lends sufficient gravitas to its lofty ambitions. While Counterpart provides plenty of gripping twists and reveals to keep you guessing, it still makes demands of its audience to think about just how our personalities are formed and what drives us to make the choices we make. It’s both cerebral and rip-roaring: enough to elevate it to the top of anyone’s watch list.

• Counterpart is streaming now on Stan. For more recommendations of what to stream in Australia, click here