The Netflix sci-fi is back after a three-year wait, with its young stars now in their 20s – and the first four episodes of this final season suggest an "all-time ending" is in store.

It's almost hard to believe that a decade ago, the concept of the Upside Down didn't exist. Such was the storytelling skill of the Duffer brothers in conceiving Stranger Things, that from the very first series in 2016, the fantasy world they created, and its lore, felt fully realised.

Warning: This article contains mild spoilers for episodes one to four of the new series

And while the show was heavily indebted to films like The Goonies and ET, very quickly Stranger Things proved it was worth far more than the sum of its parts. The 80s-set sci-fi following a group of young friends, protecting each other from the dark forces that have sprung from a portal inadvertently ripped open by a sinister human testing lab, is now one of Netflix’s most-watched series of all time.

It has also led to a whole franchise of spin-offs and tie-ins, including a prequel theatre show (Stranger Things: The First Shadow) and an upcoming animated series (Stranger Things: Tales from '85), plus board games, comics and clothing lines. On top of that, it has made superstars of its young actors, including Millie Bobby Brown – who plays Eleven, the girl with supernatural powers, held captive in the cruel living science experiment – Sadie Sink, Finn Wolfhard, Gaten Matarazzo, Caleb McLaughlin and Noah Schnapp.

But back in 2022, it was announced that this fifth season would also be its last. Despite it being a globally successful juggernaut, it's a fitting time to wrap up the series, not least for the reason that the original "kid" leads are now mostly in their early 20s. Perhaps because of this, the final season, set in 1987, sees the kingpin ghoul, known as Vecna, Henry Creel or One (played mostly under gruesome prosthetics by Jamie Campbell Bower) targeting a new generation of children, presumably to tug on viewers' heartstrings a little further.

There's one child in particular, Holly (Nell Fisher), that Vecna takes a shine to in his newest form, who appears as an imaginary friend, and stalks people's minds. Holly is the younger sister to Mike Wheeler (Wolfhard) and Nancy (Natalia Dyer). They and their peers' mission in the opening four episodes of this series, released today........

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