The Assassin: Keeley Hawes is killer in new TV series about retired, middle-aged hitwoman

Why are we so fascinated by assassins? Do we just appreciate someone who’s competent at their job, no matter how morally objectionable?

Or is it their ability to separate themselves from their victim’s humanity? Certainly makes things cleaner.

Perhaps it’s because these ruthless gunslingers, no matter how detached and professional they seem to be, always get tripped up by that most human thing of all, emotions.

John Wick, retired, gets his vengeance on when his puppy is killed, the fastidious unnamed assassin in David Fincher’s The Killer springs into action when his partner is assaulted, Leon the Professional dies because he’s trying to protect a 12-year-old girl.

Rare is the assassin whose backstory is never revealed – the original Day of the Jackal is one, although the reboot series with Eddie Redmayne gives him a family.

Assassin characters offer what we love to see in a story – a redemption arc. It’s the optimist’s ideal, that things and people can get better, that even the worst person, doing the worst thing, has good in them, and that if you can just pull the correct levers, the world will be a better place.

Also, they’re played by, for the most part, super attractive movie stars, and we like pretty people.

British actor Keeley Hawes is not the first person you think of when you picture a hitwoman, thanks to pop culture’s propensity to cast these characters as young honey traps - think, Ana de Armas, Scarlett Johansson and Anne Parillaud.

Her character Julie, a middle-aged retired assassin, is far more interesting than her younger counterparts. She has a nuanced weariness that comes from experience, rather than some traumatic childhood history.

Julie has spent years living on a small Greek island, largely isolated from a community in which she’s known as a bit of a grump. She has a tense relationship with her adult son, Edward (Freddie Highmore), a journalist who is visiting his mother. The two haven’t seen each other in some time.

It’s not the easiest of relationships, but there is a reluctant softness there – Julie seeks out the wagyu beef Edward remarked on last time he was there, only for him to declare he’s now a vegan.

Edward’s arrival converges with two events. The first is that Julie is contacted by her old handler, who offers her a fat contract to assassinate a young woman on a nearby superyacht. Something doesn’t smell right and Julie discovers it’s an impostor on the phone. She doesn’t pull the trigger.

The second is a village wedding the next day, at which she and Edward are guests, is attacked by gunmen. Everyone is killed except for Julie, Edward and local butcher Luka (Gerald Kyd).

Complicating matters is Edward’s fiancée, Kayla (Shalom Brune-Franklin) and her brother Ezra (Devon Terrell), whose dad Aaron Cross (Alan Dale) is an Australian mining billionaire who smells more than a little dodgy.

The Cross family, and something involving the codeword “chantaines”, which sounds a lot like both “Ben 10” and “Sean Penn”, are caught up in whatever is going on with the attempt to bump off Julie.

Across six episodes, it’s a mad dash around Europe trying to uncover a complex plot that also involves an imprisoned IT specialist (David Dencik), Julie’s former assassin mates (Jack Davenport) and an odd woman who knows her way around some art supplies (Gina Gershon, playing unhinged, as almost always).

The show is a funnier-than-expected lark that delights in the family dynamics at play. Even in a pressure-cooker situation, there’s always room for bickering and sniping about old resentments.

It delights in the testy mother-and-son relationship between Julie and Edward, and Hawes and Highmore are a good match – she’s no-nonsense and practical and he’s a much more sensitive soul. Fun little reveal – before discovering his mum’s true vocation, he had been told she was a head-hunter.

That’s the kind of wry humour threaded throughout The Assassin, albeit the show becomes much more of a by-the-numbers action thriller in the second half.

Then there’s the Crosses, who follow the current trend that uber-wealthy families are unhappy ones. Dale, a Kiwi that we have more-or-less claimed as one of our own after his turn as Neighbours’ Jim Robinson, always gives moral ambiguity, his characters really could swing either way, as in, you could believe he may have put a hit out on his children.

Terrell and Brune-Franklin, both WA kids and using their natural accents, are convincing as siblings who are more often than not, pitted against each other. Terrell is called on for a decent amount of comic relief as the screw-up Ezra, who sometimes makes big decisions while high on ketamine.

The first half of the series has more energy and pep as it morphs into darker tones towards the end and loses steam off a promising start.

But it’s still an amusing ride that clips along at a pace, and there is something of a redemption arc, even if the explanation for everything is more than a little silly.

The Assassin is streaming on Stan from July 24