It is probably quite an effort not to be on television if you are Terry Wogan. Offers must just flare up, whenever you stop concentrating. Weekend off, out for brunch, go for a walk and, whoops, you're midway through a faintly nostalgic 17-part digital chat show, on which you have to interview David Icke, again. The natural state of water is liquid, the natural state of helium is gas, and the natural state of Terry Wogan is being on telly. He probably only goes on Radio 2 to stop it happening.

Well, he's slipped up. This week, Terry returns (in a sort of not-really-ever- having-gone-away type fashion) to our screens with Wogan's Perfect Recall. It's a game show, it goes out in what used to be the Richard and Judy slot, and there is some sort of twist that involves lots of questions having the same answer. I can't tell you any more than that, because they haven't filmed it yet.

Speaking thus in sheer ignorance, I'm harbouring doubts. Sir Terry is a good thing, as evidenced by both his “national treasure” status and his traditional immunity from all accusations of wig-wearing, but I'm not convinced that the game show, even Blankety Blank, is his natural forte. The wit of Wogan is a meandering, free-form thing. His radio show may often sound like one stoned haiku after another, but it's the cumulative effect that makes it all work so well. It is a monologue that feels like a conversation and, at his best, you suspect he would sound exactly the same if nobody was listening at all. He's the parrot, under the blanket.

His Eurovision voiceovers were the same - the last broadcast of the last lighthouse keeper on the last island of sanity, wryly keeping his head in a raging ocean of au pairs, matadors and ski instructors singing “bingly, bangly, bong”. Those endless, endless chat shows gave us a graver, more ponderous Terry, but he still came across as a man detached from the madness. Amid the terse chaos of an afternoon game show, I fear we might wonder at his point. Still, I'm probably wrong. As nine million listeners would vouch every morning, and the man never fails. Although Wikipedia does tell me he was axed in 1992 in favour of Eldorado. Ouch.

In the evenings, meanwhile, we have The Last Word, a three-part series from the writer and producer Hugo Blick, who has brought us a variety of cleverer-than-usual, low-key comedy efforts over the past decade. These three stand-alone episodes are all monologues, and they are all about impending death. We have Sheila Hancock playing a patient in a euthanasia clinic, Rhys Ifans playing a lonely Welsh farmer and Bob Hoskins playing a cockney gangster hitman.

I'm struggling with what to write here, because these all rest on the twists, and I'd dearly love for you to find them as startling, unexpected and shot through with wonder as I did. Be warned, at least, that they aren't comedies. They are funny, but the Hancock one (which screens first, on Monday) also had me choking on a sob, even though I watched it over a bowl of muesli at 7.45am. There are laughs, of a sort, in a dying woman recording a message for her soon-to-be-widowed husband. Still, it isn't exactly My Family.

If that subject matter puts you off, try Rhys Ifans the following night. This is the pick of the bunch. Ostensibly recording a tape for a dating agency, the taciturn farmer Huw opens up like an orchid and sends the plot spiralling off in unexpected and delicious new directions. I feel like quite the tease, being so coy, but I'd hate to spoil it. I didn't catch Ifans when he played Peter Cook in Not Only But Always, so I have always thought of him as the dopey spanner in his pants from Notting Hill. More fool me.

Hoskins's hitman, after all that, is almost a disappointment. You can't fault the performance, obviously, but Blick is far better at pulling fantasy out of normality than he is at doing the opposite. Really, though, that is just a tribute to the other two. Ultimately, if you trust the judgment of a man who bases a whole week of TV reviews on a programme that he hasn't seen, and another three that he isn't prepared to talk about, don't miss them.

Wogan's Perfect Recall, from Mon, C4, 5pm; The Last Word Monologues, C4, Mon/Tues, 10.35pm & Wed, 10.45pm. Caitlin Moran is away

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