Guarding the Queen STV, 8pm Cape Wrath Channel 4, 10pm

It might not be true that every officer in the Grenadier Guards bears a double-barrelled name. Equally, there could be Old Etonians in the regiment's ranks.

It's unlikely, though, judging by the opener of Guarding the Queen . While never over-stating the sad reality of our class divide, this deft little three-part documentary series couldn't overlook the British Army's caste structure.

Our introduction to Guarding the Queen's sharply-delineated cast of players thus at one extreme included Major Marcus Elliott-Square, Major Thorold Youngman-Sullivan and the Grenadiers' commanding officer, Lieutenant Colonel Alexander Carew Hatherley.

At the other extreme was teenage squaddie Steven Cooper, a gauche young man from the English East Midlands. His initial arrival for duty at London's Wellington Barracks found him staring open-mouthed at the big-city shop windows visible from his taxi.

"Sausage and mash, £6.75!" he gasped in a flat, faintly Brummie tone, utterly incredulous. "Fish and chips, £7!"

There were plenty more telling serio-comic vignettes on offer. You couldn't help learning things, too. What did we learn? That a Guardsman's famous black bearskin cap begins as a Canadian bear's brown fur. That some of the musicians in the Band of the British Grenadiers are now women.

It was also good to be reminded that the Grenadier Guards have an all-too-real military function nowadays, quite apart from their ceremonial one outside Buckingham Palace. A forthcoming regimental posting to Afghanistan was predicted by one officer, with typical military sang-froid, as likely "to be pretty crunchy and emotional". Sadly, three young Guardsmen lost their lives in Afghanistan in May and June.

The funniest bit was young Steven Cooper and his three fellow newcomers being quick-marched into Major Thorold Y-S's office for an official welcome. On the company sergeant major barking "left turn!", three of the hapless new boys turned right, presenting their unimpressed boss with a view of their backs.

There was another lovely moment as young Guardsman Cooper made his bearskinned public debut, standing rigidly immobile for tourist cameras outside St James's Palace. His proud mum naturally took a snap, too, persuading his little sister to stand next to him and hold his hand.

Obeying Grenadier tradition, Guardsman Cooper remained stock still, staring fixedly into the distance - until the camera focused on him affectionately squeezing little sis's hand. I hope young Steven doesn't get into trouble for that. I also hope he comes back from Afghanistan safe and well.

After Cape Wrath's first intalment, one critic described it as "Wisteria Lane, Peyton Place and Stepford relocated to Brookside Close." In truth, nothing could be that bad.

Cape Wrath certainly is bizarre, though, not least because its Liverpudlian suburban setting - clapboard houses clustered round a lake - evokes Florida rather than Merseyside.

Then there's its GP, Dr David York, whose ante-natal bedside manner was somewhat comprised by his evident lust for his female patient. There's the strange teenage boy who wears his sister's clothes (it's not so much the cross-dressing that singles him out as odd in Liverpool, more the fact that he doesn't like football).

Plus there's Detective Sergeant Wintersgill with his Bengal Lancers' chinstrap moustachio. Investigating the murder of randy handyman Jack Donnelly, Wintersgill has an unusual aide: Jack's ghost "Bags packed. No Jack. Now the mirror's cracked. I smell foul play," raps Wintersgill, played with relish by Ralph Brown. Cape Wrath: Brookside scripted by Allen Ginsberg.