The Walking Dead: Dead City … ubanised zombies take over New York. Photograph: Peter Kramer/AMC

Being surrounded by a zombie horde banging at your windows feels like an apt metaphor for the recent overwhelming surge in spin-offs from The Walking Dead. The original series ended in 2022 after 11 seasons but soon returned from the grave with an expansion strategy to keep the undead apocalypse ticking over: various fan-favourite characters would headline their own six-part series.

The Walking Dead: The Ones Who Live offered the catharsis of seeing long-estranged couple Michonne (Danai Gurira) and Rick (Andrew Lincoln) reunite. The Walking Dead: Daryl Dixon took an even bigger swing, relocating Norman Reedus’s soulful redneck to rural France.

The Walking Dead: Dead City is the last of the current spin-offs to arrive in the UK but, confusingly, was the first to launch in the US last year. At least the premise is scrawl-on-a-beermat simple: bitter enemies Maggie (Lauren Cohan) and Negan (Jeffrey Dean Morgan) are off to zombified New York City. Perhaps they should have subtitled it Rotten Apple.

Maggie was the farm girl who fell for Steven Yeun’s sweet Glenn, their love a rare bright spot in The Walking Dead’s benighted world. Negan was the smarmy, soliloquising bad guy who kicked off season seven by bludgeoning Glenn’s skull with a baseball bat. That brutal inflection point in the original show’s timeline is, anecdotally, when many viewers decided to stop watching.

So credit to Dead City: even if you never kept up with latter seasons of The Walking Dead, the thought of Maggie teaming up with Negan is a great hook. Why would she do it? Again it is tied up with Glenn: their son Hershel (now a young teen) has been kidnapped as collateral by violent raiders based in Manhattan. Maggie realises Negan has history with the gang and needs his insider knowledge and ratbag cunning to mount a rescue.

For his part, Negan seems to be on borrowed time. He has a mute young orphan named Ginny in tow and is being pursued by a posse of righteous lawmen led by Armstrong (Gaius Charles), a cowboy who will prove a thorny foe.

After stashing Ginny with Maggie’s community, the odd couple sets sail for the Big Apple. Manhattan was apparently a centre for the original viral outbreak; the panicked military response was to isolate and abandon the island. Hershel is being held by a ruthless warlord known only as “the Croat” (a ferrety turn from Zeljko Ivanek), who lost an ear the last time he tangled with Negan. Like Billy Joel, the Croat has taken up residency in Madison Square Garden. Unlike Joel, he is protected by bike-helmeted henchmen and a groaning perimeter of undead.

Maggie and Negan have connected with some harried local survivors – who seem suspiciously jacked for subsisting on roast pigeon

After infiltrating the city under cover of darkness – a sequence that is creepy, atmospheric and presumably kinder to the budget – Maggie and Negan must adjust to the threat of urbanised zombies, who have a tendency to topple off towering rooftops and splatter into sidewalks. There are also homemade ziplines, hidden man-traps and swarms of cockroaches to cope with (the usually verbose Negan assesses the latter and retreats with an emphatic, hilarious: “Nope!”).

By the midway, Maggie and Negan have connected with some harried local survivors – who seem suspiciously jacked for subsisting on roast pigeon – and cooked up a rescue plan. Negan also seems to have tapped back into the theatrical sadism that, he claims, is the best way to wrongfoot opponents, setting the stage for a rematch with the Croat. With his silverback bearing and bourbon rasp, Morgan has the chops to sell such an unsettling mix of calculating pragmatist and exuberant monster.

It is a tougher role for Cohan, as Maggie is so single-minded about saving Hershel that all her usual warmth and empathy has hardened into cold, barely contained fury. “She’s tougher than she looks,” says Negan to their new allies, “and she looks tough as shit.” Maggie has even weaponised her cherished wedding ring, and the looks she throws at Negan are as lacerating as her spring-loaded boot knife.

But that frenemy energy between the leads is what helps this series rattle along like a disreputable B-movie. If it cannot match John Carpenter’s blackly comic Manhattan suicide mission Escape from New York – an obvious influence – it at least has fun trying.