So I was coming home from the shops the other day and who should I see walking towards me but Jack Nicholson, with two leggy blondes on his arms. I stopped him and asked if I could take a picture of us together on my mobile phone, we got chatting and, would you believe it, he invited me to lunch at Nobu! That was great, but then as I was going to the toilet, a waitress beckoned me into a broom cupboard where...

OK, OK, that was a cheap trick. I know that, by now, you will have seen the picture and realised that, this week, I shall be telling you all about a Lexus diesel. BUT WAIT! DON'T GO! The new IS220d is really, really interesting, honest.

The brochure says it is the "latest expression of the L-finesse design philosophy", and that Vehicle Dynamics Integrated Management is standard on the Sport version. It has the world's first dual-chamber front-passenger airbag too, and it's the first in its class to have knee airbags.

And, um, well, that's about it really. To paraphrase John talking about Ringo, the IS220d is not the best four-door saloon in the world; in fact, it isn't even the best four-door saloon in the Lexus range. But it does still have a great deal to recommend it. There's the usual reassuring build quality, for instance. Lexus doesn't just make cars, it sculpts eternal monuments. Nobody does clinical, soulless efficiency better than Lexus, and its cars regularly top the JD Power surveys, so you know from the start that this is a car that will last longer than the Duracell bunny. Come the apocalypse, when talking monkeys rule the planet, Charlton Heston will glimpse a Lexus badge in the rubble and, realising the truth of our environmental folly - that we didn't do enough to cure bovine flatulence - he will start it and drive off.

Where was I? Actually this is an important car: this is Lexus's first-ever diesel - long overdue in a market sector dominated by oil burners - and its first four-cylinder engine. It is quick, frugal and "gutsy in the low range", as Autocar might put it.

Unfortunately, it still sounds like a 1970s Mercedes taxi and no amount of gears (it has six, by the way) are going to hide that. You would think that, having taken Lexus so long to develop a diesel, it would have come up with something special (it has just unveiled the world's first hybrid luxury saloon, the LS600, for instance), but this is an old-school diesel - or at least, that's how it will sound to the neighbours on a cold winter morning.

The best-of-breed BMW 320d is more refined; it will eke out a gallon for an extra seven miles; and, crucially, its cleaner emissions mean that it ranks three tax bands beneath the Lexus. Bearing in mind that these are the kinds of cars that are bought by accountants - either for themselves or as part of a company fleet - one can imagine the Lexus might struggle.

It doesn't get much better on the motorway where the engine continues to intrude like a kind of coarse, low-level tinnitus. Thank heavens for the "Mark Levinson" stereo, which turns the IS220d into a mobile concert hall. I have no idea who Mr Levinson is, and I have never seen his name outside of a Lexus cabin, but he makes a damn fine wireless. If only the car that carried it was as impressive.

It's a classic: Lancia Stratos

Lexus has only been around for 15 years in the UK so, as good as its cars usually are, none can really yet be called classic.

So, in another desperate attempt to keep your attention, here is another car that begins with "L" - one of my all-time favourites as it happens - the Lancia Stratos.

Launched in 1973, the Stratos was an amazingly futuristic-looking rally car, powered by a mid-mounted Ferrari V6 (from the Dino) and with lightweight glass-fibre body panels. The result was one of the greatest, and certainly most beautiful, rally cars ever.

It won the World Rally Championship three times in a row from 1974-76, but that success never translated into great sales. Five years after Lancia stopped making them, it was still trying to flog the last of the Stratos road cars (the fact that they were terribly hot and cramped inside and had virtually no luggage space might have had something to do with it).

Today things are rather different and the Stratos is one of the most desirable Lancias ever made, with prices nudging £60,000.