Last Night's Television - Doctors and Nurses at War, ITV1; Ladies of Letters, ITV3

"Double-check you've got your passport with you," said an officer with a clipboard, doing a roll call for the members of 203rd Welsh Field Hospital as they prepared for mobilisation in Doctors and Nurses at War. It seemed an odd requirement for a unit preparing to head for the front line. What happens if you've left it at home? Do they punish you by refusing to let you go and get shot at? It made me wonder whether they have to fill in an immigration card as well, shortly before corkscrewing down into Kandahar. Address in Afghanistan: Camp Bastion. Purpose of Visit: preventing fellow tourists from going home in a box. Duration of Stay: three months, with any luck, but the Taliban may decide otherwise.

That a kind of tourism is in play here was acknowledged by Colonel Phil Hubbard, who runs the military hospital in Camp Bastion. What persuades NHS doctors and nurses to volunteer for the Territorials? he was asked, and he replied that he thought it was "the attraction of using their skills in an environment that is unusual to them". This sounded a bit odd, too, to an outsider, until you realised that they weren't exactly getting away from the day job in most cases, only doing it in a different place. And with different people. Captain Sue James, a kindly grandmother, made it sound as if she'd signed up as a "weekend warrior" for social reasons. "The camaraderie is quite different from what you get in the NHS," she said, shortly before setting out.

That might have something to do with the increased prevalence of suicide bombers, I expect, one of whom made his contribution to team-building togetherness shortly after the 203rd arrived in Afghanistan, by detonating his vehicle just outside the compound wall. Fortunately, the soldier on the checkpoint at the time wasn't badly hurt, but it wasn't very long before the team got a grimmer introduction to the reality of the war after another selfless jihadi targeted civilians in Musa Qala in the hope of luring a medical helicopter to ferry out the casualties. As the Chinook took off for the return flight, it came under attack. And while a city-centre ER room can get seriously unpleasant on a busy night, they don't very often take incoming rounds, and you don't have a door-gunner firing back as you do basic triage.

"The battle between high explosives and the human body is a pretty one-way affair," said one of the regular Army surgeons, pressed to this bitter understatement by the arrival of Rahima, a five-year old girl whose right arm had been blown off in the attack and who had serious stomach wounds as well. Had it not been for the skills and dedication of the Army doctors, she almost certainly wouldn't have survived, and she certainly wouldn't have received the complicated skin graft that gave her a chance of being able to use her remaining hand. It offered a slim kind of counterpoint to the horror of her injuries and an occasion for patriotic pride, until the niggling thought occurred that she wouldn't have been injured at all but for the British Army's presence in her home town.

It may have been something to do with Doctors and Nurses at War, but I couldn't help watching Ladies of Letters as if it was a frantic and ultimately fruitless attempt at resuscitation. Based on a book and successful radio series, it consists of an exchange of letters between two elderly widows, the joke (such as it is) depending on what is never quite stated in their peerlessly vacuous correspondence. Unfortunately, while doing an epistolary narrative such as this on radio is like falling off a log, doing it on television – with Maureen Lipman and Anne Reid taking the part of Irene and Vera – is an absolute nightmare.

For one thing, you have to decide what your correspondents are going to do while they're "reading" their letters. Do they look at a writing pad or at the camera, and if it's the latter, then what part are we supposed to be playing in the thing? What on radio is a dialogue by other means becomes a pair of monologues flying in clumsy formation. What's more, nervous that comedy won't emerge from between the lines naturally, the producers have contrived a kind of forceps delivery. The line "I tried your taramasalata dip on the vicar's wife and she said she'd never tasted anything like it" provokes a monochrome flashback of a woman throwing up into her handkerchief.Or comedy sound effects are added to the memory of a mishap with a garage door. Or the performers are encouraged to overact wildly in an attempt to shock the thing into life. "Gerald always had a sweet tooth," wrote Vera of her late husband, and then, quite inexplicably, flung a pat of cake mix at his photograph. They tried everything, but it was dead on arrival.