NETFLIX always throws up surprises. Clicking it open is like pulling back the lid of an old chest found in granny’s attic: will it contain wonderful old photos, classy vintage dresses and priceless brooches, or just her old Avon catalogues? There’s no way of knowing; you’ll just need to rummage around.

So it is with Netflix, which has its share of obscure shows, wonky documentaries and films such as Lesbian Vampire Killers, yet also contains wonders like House of Cards, Better Call Saul and The Unbreakable Kimmy Schmidt.

And if you don’t want to commit to a series, you can dip into an episode of the mammoth Ken Burns documentary on the American Civil War, or relax as cheery Bob Ross paints you a mountain range.

Everything is here, but the sheer variety makes it hard to discover something new. You can’t find a show by chance because you’re lazily channel hopping, and there are no Netflix TV listings printed in the papers. Instead, you just need to dive in and hope to get lucky, or keep your eyes peeled for recommendations from trusted friends and knowledgeable critics (ahem!).

During the week, I found a series on Netflix which I’d never heard of, and which seemed too good to be true. When I Googled it, I found a brilliant director and cast — and yet no-one’s talking about it. Strange.

The Same Sky (Netflix) is similar to Channel 4’s Deutschland 83. There! That tells you instantly what you need to know, and whether the show will appeal to you.

It’s set in East Germany in the 1970s and is about a “Romeo agent” from the Stasi who is sent west to seduce an unhappy woman working in Nato intelligence. The blonde and beautiful target is played by Sofia Helin, best known as Saga from The Bridge, and her Stasi seducer is Tom Schilling, a German actor who has played a young Adolf Hitler.

Most promisingly, the series is directed by Oliver Hirschbiegel, responsible for the Oscar-winning Downfall, about Hitler’s last days in the bunker.

The Cold War is back in vogue. We’ve had a nice few years of relaxing into peace, assuming it was “the end of history”

and things would, inevitably, be fine from now on, and we’d no longer lie awake at night listening for the four minute warning. But we’ve botched it, haven’t we?

The former tensions come creeping back.

This revival of the old nuclear horror partly explained the recent success of Deutschland 83, so why aren’t we seeing the same interest around The Same Sky? Is it perhaps just not very good?

I’ve only watched one episode and, despite being a sucker for a good Cold War thriller, and loving the stark Stasi style of the Commie East, I wasn’t enraptured by it. However, I’m going to stick with it, partly because the subject, cast and director are surely too good for this to fail, but also because this is Netflix and shows move at a different pace here. There’s no need for constant cliffhangers to make sure we tune in next week. I’ll cut it some slack. The show opens at the Stasi training school where a classroom of men — some more appealing than others – is being taught the arts of seduction so they might penetrate the West, and its women, and prise secrets from them.

This is Stasi seduction so it’s not about hearts and flowers but instead concerns itself with strict rules on eye contact and the left side of the brain.

Behind the stern lecturer is a blackboard with a diagram of the naked female form. It seems the Stasi don’t do sexy.

The most handsome of the bunch, Lars Weber, is summoned for a special assignment. He’s given a new persona and will be sneaked into West Berlin to target the pretty but troubled Lauren Faber. Despite her anxious home life — she lives alone with a sulky and violent teenage son — she has a top job working with Western intelligence and holds a million juicy security secrets.

Can this “Romeo agent” coax them from her?

The action happens fast: Lars is soon in a cafe watching his target. He is careful to make the required lingering eye contact, then he abruptly leaves; Stasi advice is to be first to break the meaningful looks as this leaves the little lady hungry for more.

The costumes are brilliant, and the sets, especially in the East, are so evocative: those poky, claustrophobic flats thrown up in their endless thousands for the workers; the drab, repetitive patterns on the wallpaper; and the limp, colourless fabrics.

The stifling East Germany was brilliantly conveyed, as were the endless little nibbles and nags of the authoritarian state: don’t play music at night, don’t watch American cartoons, turn your TV aerial away from the decadent West!

But, putting the atmosphere and scene-setting aside, where was the story? For a drama about the “Romeo agent” Lars, and his cruel seduction of Lauren, they hardly made an impact.

They were swamped by too many other characters who were all battling their way on to the screen to lay their own stories before us. Lars and Lauren seemed lost in all the texture and intricacy.

But I’ll go back for more, simply because it seems too big to fail.