Last Night's TV: Little Ships, BBC2<br />Pulse, BBC3

I've noticed something about Dan Snow. He doesn't – ever – just present something straight. He always has to be doing something: sailing, hiking, driving, standing on his head. Maybe not the latter. Even when he is sitting still, he's not just sitting there. He's leaning into the camera, whispering conspiratorially. You know what I mean. He's just a very... active kind of presenter, isn't he?

Anyway, there he was last night, leaping in and out of cars, on and off boats, and in between trees, all while presenting Little Ships, the BBC's documentary to mark the 70th anniversary of the Dunkirk evacuation. Not that he was doing a bad job of it. Quite the opposite, in fact. He was actually very good indeed: engaging, lively, reassuringly authoritative. A lot like that inspiring history teacher you didn't get at school but wish you had, especially so that you'd be in a better position to pass judgement on television documentaries like this. Ah well! Better late than never.

And what a coincidence that Snow should be the one to step into the breach; after all, wasn't he recently embroiled in a Dunkirk of his own? Last month, I think it was. Much to the annoyance of the French authorities, he tried to send his very own flotilla of "little ships" to rescue tourists stranded by the ash cloud at Calais. Oh, never mind, I've just looked the whole thing up. It's not a coincidence at all; according the BBC (who should know, being, in this instance, his employer) his actions were inspired by filming this very programme. Inspired by, but not as successful as. In the event, he was turned away empty-boated by French officials. Zut!

But to the point: last night was really very good indeed. Flicking between accounts of Hitler's actions on the Continent, goings-on at Westminster, and interviews with Dunkirk survivors, Snow captured the operation's urgency and scale very nicely. Footage of troops blowing up bridges was accompanied by maps of German strategy and clips from the BBC World Service announcing Belgium's appeal for Allied help. In one particularly moving encounter, we met Harry, one of the "little ships" stewards. He remains disarmingly unimpressed by his own bravery but was clearly very moved by a plaque, pointed out to him by Snow, commemorating his fallen colleagues. "I knew Stokes," he remarked reading through the list of deaths, before putting his hand up to the board, giving it a swift tap, and walking away teary-eyed. It's quite remarkable, the sense of inevitability, of duty, that these men felt about the whole thing. "Did you know at all what you were letting yourself in for?" asked Snow of one of Harry's colleagues. "Ha. We had a rough idea," he replied. "I think it was a fiver we were offered to go over to France. Five shillings."

I struggle to eat dinner during Casualty, so Pulse looks likely to come in useful if a quick-fix diet is ever in order. True, it's only a pilot at the moment, though I can't imagine it will be too long before a full series appears, barring indignant protest at the sheer horribleness of the whole thing (Chain-saw surgery! Living bodies in the mortuary! Milky-eyed patients returning from the dead! All on the NHS!).

Claire Foy played Hannah, a trainee doctor seemingly struggling with the death of her mother. Recently, we learned, she went "a bit nuts" during an operation, and things hadn't appeared to have improved since. She saw visions of her mother everywhere, and jumped away screaming after imagining that a patient's tumour was moving. But wait. What's this? Could it be – duh duh duh! – that it wasn't just her imagination? Maybe there was something sinister going on!

There was, of course. And to tell the truth, we should have known from the beginning. For starters, said tumour belonged to Charlie, a virtual medical miracle. He'd contracted the same disease five times, every time recovering to full health before – bam – it returned. And Hannah was clearly not nuts. After all, she was the first to question her sanity, and isn't there some rule about that? If you think you're mad, your not. Hm.

Anyhow, accompanied by a delightfully hammy series of horror sound effects (THUD went someone on the cymbals when our heroine ran into her creepy ex-boyfriend on a corner), Hannah uncovered a covert series of trials going on in the hospital. The aforementioned creepy ex, Nick, played chillingly by Stephen Campbell Moore, was at the heart of things, infected with the same gruesome flesh-eating disease that doctors were administering to Charlie. He had been injecting his hand with God knows what to hide the gaping wound, but was in rapid decline. To complicate things, he was keeping the whole thing secret, speaking only to his video diary, while also trying to two-time his current squeeze with Hannah.

It was all jolly good fun: lots of creeping around darkened hospitals, and a lovely, slasher-esque scene in the library, with Hannah being chased by a solitary tormentor who kept flicking light switches and stealing her notes. It was not, at all, the sort of thing one expects from the BBC. It was almost American, not a million miles away from the shock-and-gore of Wes Craven. And it was terribly corny, too: full of schlocky horror clichés and well-worn suspense-builders. Still, I liked it. A lot. It was refreshing, and bold, and a break from the norm. So yes, if you're reading this, BBC controllers: please, sirs, can we have some more?

a.jarvis@independent.co.uk; twitter.com/aliceazania