It is always difficult to review a comedy, for the blindingly obvious reason that not everyone finds the same things funny. There are people who think that Samuel Beckett's plays are thigh-slappingly hilarious (and that those who don't are just thick), and millions howl with laughter at Mrs Brown's Boys (and think those who don't are snobs).

Political satire is different, though. Although whether you get a laugh is one measure of its success, there are others. One of them, for me, is how often you suspect that the libel lawyers had to be called in, followed by wondering how uncomfortable the people portrayed feel as they see themselves on screen.

My guess, after watching the first episode of Irish Pictorial Weekly (RTÉ One, Sunday), is that the series’ lawyers are collapsed in a heap of overworked exhaustion, and that people such as Taoiseach Enda Kenny and Minister for Agriculture, Food and the Marine Simon Coveney, as well as the Garda, the Civil Service and other arms of the State, are squirming.

Irish Pictorial Weekly is splutter-your- tea-across-the-room hilarious, as it holds up a mirror and finds, at best, cack-handed carry-on in officialdom and, at worst, rampant hypocrisy.

There isn’t a dud sketch in it; kudos to the large writing and acting team for stuffing the programme with sketches, although with just a six-week run they have a lot of material to fit in. The use of existing footage – clips from RTÉ news revoiced or reworked – has gotten slicker since the first series, and the self-serving civil servants less surreal (although the bizarre wigs remain), with sharper satire.

Some sketches, particularly the commentary on recent news events, are so close to the bone that marrow is leaking out, such as the balladeer Dominic Walsh (Paul Woodfull) crooning There's a Bed in Me Shed, a hokey country number that for a split second seems pleasant enough; then you tune into the lyrics of what turns out to be a song about IRA safe houses: "You might be a paedo, but you're Provo, nuff said."

Then there is Tara Flynn's comely maiden, singing sweetly about women being just vessels, worthless without a baby in them, and advice on money management from David Drumm (Paul Howard); it's basically a cash-lodgment scheme called Awife.

You have to like Louis Theroux to watch one of his films, because he puts himself in nearly every frame. His persona used to be that of the wide-eyed bystander. He has dropped that now. In Louis Theroux: Not Guilty By Reason of Insanity (BBC Two, Sunday), in which he visits state psychiatric hospitals in Ohio, he is more knowing and more empathic as he talks to inmates whose legal defence centred on their mental health.

His technique is to introduce the people before finding out more about their mental issues. There’s Jonathan, a reserved, well-spoken young man; an elderly grandmother type, Judith; and Eric, a former TV evangelist on the brink of being discharged.

Then, through Theroux’s relaxed, quiet conversation, we learn that Jonathan slit his father’s throat seven years previously; Edith tells us that a stabbing on a bus was nothing to do with her and that she is the reincarnation of Jesus Christ; and Eric is so terrified of facing the outside world that he has a panic attack as he leaves.

A diagnosis of schizophrenia is common to all – although some have additional mental-health difficulties – and the queue as the patients line up for their tablets hints at how heavily medicated Theroux’s interviewees are.

Most screen time is spent with Jonathan. There is the shock value of seeing newspaper reports of his crime, a photograph of his jovial-looking academic father, and photographs of his killer as a happy and adorable boy. These are contrasted with Jonathan’s expressionless description of calling to his dad’s house and calmly slitting his throat.

You’d think a killer who has been in therapy for years would have been asked every question there is, but Theroux – and this is what makes him so compelling to watch – asks one question that, extraordinarily, given the circumstances, he has never been asked before: “Did you love your father?”

The last Louis Theroux documentary I saw was about dogs and their owners in Los Angeles – and even he couldn’t make me interested in their far-away, far-out lives. But this two-part series is a nuanced exploration of people living with profound mental-health issues and the challenges that wider society presents.

If you've seen Terry Wogan's Ireland and James Nesbitt's Ireland you have reason to be nervous about tuning into Great Irish Journeys With Martha Kearney, (BBC Two, Monday). UTV Ireland's puzzling fondness for showing creaky repeats in prime-time slots means that Nesbitt and Wogan's diddly-eye tours of their old sod got another outing this month.

But Kearney’s four-part Irish travelogue is different. We are half-way through the Dublin-born BBC broadcaster’s tour of Ireland, and there’s none of that queasy feeling of being slapped around the head with a blarney-soaked Aran geansaí.

As her reference point she is using the pencil drawings of George Victor Du Noyer, a 19th-century geologist who spent 35 years, it seems, walking every inch of Ireland, charting in a series of beautifully illustrated notebooks everything he saw. Last week Kearney went to Glendalough, where her parents went on their second date; the personal touches are lovely, as is her enthusiasm for just about everything.

This week she travels to the Giant's Causeway, and also explores the impact of the Famine on Skibbereen. When she talks about Belfast's industrial past she refers to her time there as a journalist reporting on the Troubles.

The well-chosen contributors include historians, geologists and archaeologists. That they often tramp the ground with Kearney gives the travelogue a vibrancy you never get when relying on talking heads filmed indoors.

Great Irish Journeys With Martha Kearney is a rare thing: a beautifully shot travelogue of your own country that doesn't feel as though it was made through misty eyes with the tourist market in mind.

tvreview@irishtimes.com