Last Night's TV: Giant Squid: Inside Nature's Giants Special/Channel 4<br/>Reggie Perrin/BBC1<br/>Sex Trafficking in Cambodia &ndash; Stacey Dooley Investigates/BBC3

On the (highly) scientific scale of natural squirmyness, cephalopods rank pretty high. Even grilled, seasoned with a bit of olive oil and lemon juice, they take a certain oomph to tackle. Raw, enlarged and sprawled on a dissection table... well, suffice it to say thank goodness it wasn't tea time. Not for me anyway.

"It splatters crap all over you," we were cheerfully informed as a team of biologists cut open our squid's digestive gland. Gruesome, yes, but possibly the least remarkable thing about last night's Giant Squid: Inside Nature's Giants Special. The whole series has been pretty good, but this was spectacular. Until 2006, there was scant evidence that the species even existed: a bit of blurry film footage, a quick glimpse under water. Then some Japanese scientists managed to film one on the ocean's surface. In deep seas, said Richard Dawkins, things tend to reach exaggerated proportions. Even a woodlouse (here he whipped one out) can grow as big as a cat.

Anyway, forget sharks. Imagine being eaten by a squid. Not only are they huge, flabby and – shudder – tentacled, but their mouths are like little razored plug holes. Amazingly, we know so little about them that we don't even know how they hunt. Normal-sized squid catch their prey by rapidly darting out their tentacles, before yanking the unsuspecting creature into their meat-grinder mouths, literally shredding it as they go. Giant ones might do the same (their mouths come with a built-in file, a sort of tongue with teeth, for extra mincing) but they might not. They could, hypothesised our hosts, "use stealth rather than speed", cunningly dangling their tentacles far below them until they grope a meal, at which point the hunting process is really a fait accompli, so strong and sticky are their long limbs. At the end of the day, nobody knows. Being eaten alive by a squid would, I imagine, be a lot like being sucked into a cold, wet, cement mix. Again, just a hypothesis. Whatever, it puts Jaws to shame.

Giant squid have three hearts. This is so they can (a) breathe but also so that they (b) spurt out air, jet-propeller style. They can also spurt out ink, and change colour at whim. They might – another hypothesis – be able to light up like a bulb so as to disguise themselves when silhouetted against the ocean's surface and they can also almost certainly hear. Still, their brains are minute, the size of a broad bean. Their oesophagus, oddly, runs through their brain. For all its extra-terrestrial weirdness the giant squid is not, as they say, the sharpest tool in the box. If intellect is what you're after, it's not the squid you should be looking at, it's the octopus. But you knew that already: how else could Paul have predicted the World Cup so accurately? Octopuses can be trained, can learn stuff, figure out problems. They can open boxes and navigate mazes. Thank heavens they're not as big as the giant squid. Well, not that we know of.

One complaint: an hour and twenty minutes. Was that really necessary? In a word: no. Dawkins et al were fascinating, but they would have been all the more so had they not rolled on for quite so long. They said it themselves. Little squid = delicious. Giant ones = bitter on the tongue.

Reviving Reggie Perrin wasn't a great idea when it came to the first series. The fact that the BBC has gone in for a second stab is even more mystifying. In truth, if you were a fan of it last year, you probably still will be. Not much has changed: the whiff of My Family, Martin Clunes's perpetually incredulous expression (remind me again why I'm doing this?), the decade-old can of laughter. The question is, was anyone a fan of it last year?

Either way, last night went something like this: our hero, titan of middle management, awoke to realise that flogging male grooming products was not, as it turns out, what he wanted to do for the rest of his life. And so he resigned, very publicly, displaying the sort of flamboyance that would make an internet prankster proud. And then he commenced, briefly, life as a pioneer of self-sufficiency. He drew pictures of a marrow, played with some wood and made his way down to the job centre all by himself. Along the way there was a stint as a shelf-stacker, a bout on the psychotherapist's couch, and the news that Reggie's father was soon to marry his mother-in-law. Meh.

It was while dragging my heels from the sofa to the DVD player that I realised I didn't particularly want to watch Sex Trafficking in Cambodia – Stacey Dooley Investigates. Don't get me wrong: I like Dooley. I gave her programme last week (similar format to last night's, only it was child soldiers in the DRC, rather than underage sex slaves in Cambodia, that she was "investigating") a good review. It's just that she's best in small doses. She's totally charming, her fresh-faced enthusiasm as emphatic a foil to the blank-eyed despair of Phnom Penh's working girls as ever. Still, I'm not sure I could handle a whole series of her unfiltered yoof-speak. Once a year, as things are, well... that's just about perfect.