Death Row, Channel 4, Thursday Hit The Road Jack, Channel 4 Tuesday

Condemned prisoners face death with aplomb and a milkshake in Herzog's candid documentary

It seems the purgatory of awaiting the death penalty is a subject too painfully sprawling even for Werner Herzog to cover in one film. So Channel 4 is showing a sister project to his recent feature-length documentary, Into the Abyss, a four-part series entitled Death Row, in which the idiosyncratic German film-maker further explores the in-limbo lives of Texan prisoners.

In part one, Hank Skinner insisted he was not guilty of bludgeoning his girlfriend to death and fatally stabbing her sons. As we hear Herzog making clear to Skinner – most of the episode is recorded from his point of view, the camera resting on Skinner through the visiting-hours regulation glass – the film will neither campaign for him nor condemn him. (Herzog does, however articulate, in that wonderfully slow, stable and strange voice, his own view: "As a German ... I respectfully disagree with capital punishment.")

Skinner has been banged up for 17 years, and already got within "five steps" of the final gurney, where he would be strapped down and given the lethal injection. A stay was issued as he was eating his last meal. You might expect a haunted, gaunt figure but no – while Skinner may have an unusually expressive, twitchy face, it's mostly pulled into fleshy grins. Of eyeing up his own deathbed while slurping a milkshake, he claims: "I wasn't bothered by it at all." And you can believe that; he's matter of fact and personable, talking about his execution date as we might discuss a parcel delivery. Which sounds psychopathic in itself – but what Herzog captures is the mundaneness, and the gallows humour, that characterise death row existence.

All of this is refreshingly non-judgemental, low in handwringing or sentimentality. Which is not to say that Death Row isn't creepingly unsettling. There's something oddly touching about Skinner's dreams of freedom; suddenly the weekly supermarket shop really does sound like a bountiful heaven, and a washing machine is a miracle. Herzog also films the road between the regular jail and the "death house", and finds in that prosaic journey through desolate Texan backwaters a sense of the ordinary world turned extraordinary, as if seen by a man for the last time. As Herzog puts it: "Everything out there suddenly looked magnificent."

On another, truly tedious, journey was Jack Whitehall, whose comedy roadshow Hit the Road Jack began in Cardiff. I couldn't have been won over more decisively by Whitehall's stint as student toff in Fresh Meat; it was spot on, very funny, and that bit with the dying horse unexpectedly slayed me. No wonder they gave him his own show.

But Whitehall is evidently only as good as his script, and this one stinks. First he does a bit of stand-up at Blaenavon Workmen's Hall; his "posho visits the provinces" schtick goes down well live, if not on-screen, with material about the Welshness of Doctor Who, in which he compares the tardis to a Welsh girl's vagina ("you wanna see something that's bigger on the inside?").

The real volumetric mystery here, however, is his weirdly bouffant hair – what product is he using? Anyway, we flit to a bizarre, pointless interlude in which Whitehall pretends to be a rugby coach (now in a blond wig which makes him look like Owen Wilson). The team, set up to appear stupid, just look nonplussed. Later, Whitehall goes and stays with a Valleys family – stuff on male voice choirs and cameos on Welsh soap Pobol y Cwm ensue. Hilarity does not.

For Whitehall's jokes fall into but two camps: unimaginative stereotyping of the Welsh, and studenty. (He will keep on about shotting Jagermeister or downing Smirnoff Ices, when clearly he's just swallowed his own publicity). He appears to be going for a kind of gap yah colonial tour round the wilds of Great Britain – anywhere outside the Home Counties – in which we're encouraged to laugh at the natives. I can't quite believe Whitehall's this dumb; presumably he'll soon be doing interviews featuring the phrase "regrettable career choice". Or maybe he really was a one-trick pony.