Because it was made in the early 1960s, and because it involves a number of the same creative talents, City Beneath the Sea (and its sequel, Secret Beneath the Sea, also included in this DVD release), is one of those shows – like Quatermass – that’s often described as a forerunner of Doctor Who, the suggestion being that without this, we couldn’t have had the latter.

With City Beneath the Sea, it’s more difficult to make the case, as the shows don’t share a great deal stylistically or even thematically. But what is clear that City… is exactly the type of show that Sydney Newman has intended his sci-fi time traveller to inhabit: mostly education for the kids, with a bit of action thrown in to keep them coming back the following week.

If we’re honest, the action here is largely limited to hiding in cupboards/under bunk beds/behind doors while apparently half-blind ex Nazis entirely fail to spot the heroes cowering in plain sight.

In this, to be fair, City… does resemble a fair amount of pre-seventies Doctor Who in that there’s rather too much creeping down corridors for far too much screen time. It’s easy to surmise that what takes four episodes here, would take Steven Moffatt roughly three minutes.

But of course, this is television from a different time, television aimed slightly below a group that was only just beginning to form (the teenager), and in an era where a young boy’s fancy would be mainly occupied by either spaceships (hence the earlier version of this show, Pathfinders in Space) or ships (hence the significant amount of stock footage here), means that this feels entirely right, if, by modern standards, rather plodding.

The (minimal) model work is at least passable, but it all feels somewhat less than the sum of is parts. A series of Naval gazing, if you will. Obviously, it’s lovely in a nostalgic way to see these episodes – even if you weren’t even born at the time – and the musical score does a great deal of work to rack up a degree of thrilling tension that simply isn’t there on screen.

The aptly named Gerald Flood – later to play Kamelion in Davidson era Doctor Who – is an appealing lead in the great tradition of 1960’s genre leads (charismatic and seemingly already middle aged), and has a nice line in fluffing his lines while the rest of the cast stoically pretend not to notice.

The kids are worth a mention too, being personable enough while being saddled with both the script and stage-training of the wide-eyed Gosh-Look-At-That variety. However, compared to similar characters in Timeslip, which also deals with youngsters coming across government secret initiatives, these children fair less well. That’s also true of the female characters who all appear to share the surname ‘Token’.

There’s a certain charm in these serials – mainly based in how entirely uncynical it all is: the storylines and villians are only a stroke away from the Enid Blyton template of storytelling, but unless you’re a true geek proud, or a boy about to hit your sixtieth birthday, you’re likely to find this something of a frustrating damp squib.

Released on DVD on Monday 17th October 2011 by Network.

Watch a clip…