Pulse, BBC Three

Either way, I’m glad they didn’t trail this as a zombie drama because that wouldn’t have been strictly accurate and would have pre-empted the nice little frisson induced by the ending. But first things first, and Pulse follows the return to hospital of young medical intern Hannah, played by Claire Foy, who made such an impact in the title role in BBC One’s Little Dorrit. Quietly resourceful heroines seem to be her thing.

Hannah tries to overcome hallucinations of her mother dressed in an operating gown (she was a cancer doctor whose untimely death sparked Hannah’s year-long sabbatical), and get on with her training in a hospital that is dubbed “the suicide capital of the NHS”. There seems to be a sideline in unethical experiments going on in this sinister establishment, conducted by Hannah’s surgeon ex-boyfriend Nick, whom we witnessed accidentally cutting his hand during an operation – a wound that requires regular injections that miraculously turn golf-ball sized boils back into virgin flesh. Full marks to the special effects bods, but some things are best left to the imagination if you don’t want to provoke sniggers in the audience. Actually this was the only moment that jarred - not bad for a genre laden with such pitfalls.

Hannah’s natural sympathy for one elderly cancer patient leads her to investigate why Nick (played by Stephen Campbell Moore) is giving the old man nightly injections that aren’t recorded on his medical notes, and whose administration is being unconvincingly lied about. Meanwhile the boil on his hand keeps returning, and there’s the added complication of something moving around underneath the flesh on both Nick and the elderly patient’s abdomen - as if a monster was waiting to break out through their sternums in the style of John Hurt in Alien.

All this was reasonably intriguing without being all that scary – and the don’t-look-now moments were caused more by scalpels slicing flesh than by any in-built dread. The gore wasn’t overdone, to be fair, but horror tends to need at least a smidgen of allegory to elevate it from the mere slasher fare - however ingenious (or good-looking - this had an expensive sheen). Being Human contains such hidden depths - I’m not sure that Pulse does. What Paul Cornell’s script (taken from a story by Ben Teasedale, we were told) does seemingly possess is a plan - and the final shot, of Hannah’s apparently long-dead mother, wired up to a hospital bed, was laden with promise.

Hopefully we’ll get to experience it - hopefully this side of the London Olympics. And while it’s good to see BBC Three experimenting with pilots - after all, a lot of licence fee geld has been wasted on full series of utter dross - they tend to make unsatisfactory viewing, dangling its audience as if on the end of the only completed section of a suspension bridge whose construction has been put on hold. You can only wait so long for a cliff-hanger, or bridge-hanger, but at least I did feel I wanted to see whether it dropped like a stone, or whether Pulse scrambles niftily back up and goes on to be the success it perhaps deserves to be.

• Watch Pulse on BBC iPlayer
• Find Little Britain, Being Human and Little Dorrit on Amazon