What do the characters played by Billy Murray in EastEnders, Trevor Eve in Waking the Dead and various mysterious agents in Spooks have in common? Well, they’re all hardmen and essentially loners, but what really ties them together is that every one of them drives a Lexus.

The overwhelming majority of those who watch these programmes will have little idea of what a Lexus is, despite the fact that the brand has been part of the British market for 15 years. Lexus’s own figures state that the brand has just 6% awareness in Britain and it’s an issue the company is keen to address. Hence the splurge of product placements in television dramas.

“When these programmes come up and other manufacturers go away to think about it, we dive right in there — get them a vehicle straight away,” says Steve Settle, head of Lexus in Britain. “It’s cheap, it’s direct and it works.”

So expect the new Lexus IS to be gliding across your screen very soon. On sale now in 2.5 litre V6 form as the IS 250, and with the 2.2 litre four-cylinder diesel IS 220d arriving in the new year, it is the car with which Lexus plans to rattle the cage of the new BMW 3-series and raise the profile of the anonymous marque.

Visually, the IS seems more than up to it. The car’s curving lines look good when it’s standing still and great when it’s on the road. There are a few too many low-grade plastics inside, but not enough to destroy the very appealing ambience, even if room in the back is decidedly tight.

If only this excellence extended to the way the IS behaves on the road. To me the defining characteristics of a Lexus are its refinement and ride. I can recall the moment in 1990 when I first sat in the new LS 400 and had to look at the rev counter to see if the engine was turning.

Okay, the IS is a smaller, cheaper car charged with doing a rather different job than the luxurious LS but buyers will still be entitled to expect a noiseless ride, in keeping with the marque’s reputation for quality. Unfortunately they are in for a rude awakening with the IS 220d. This is the marque’s first diesel and while its rattlings may be acceptable in a Toyota Avensis (which uses the same engine), I wonder whether Lexus customers will be prepared for the shock. The problem is not with the car’s emissions or economy — which are excellent — or its rather less impressive performance. It’s simply that every time you accelerate you get an audible reminder of what fuel it uses.

I was so surprised by this that I asked Lexus to supply me with another car just in case the one I’d been driving had some mechanical fault. The second car seemed quieter, but still far from what you’d hope for. I’ve not driven them back to back, but I know such dark thoughts didn’t enter my head when driving four-cylinder diesels from the likes of Jaguar, BMW and Honda.

Nor does the IS 220d enjoy the ride quality you might expect. The suspension has been set too stiff, so while the handling is truly excellent you find yourself keeping a sharp eye out for potholes and other imperfections.

Switching to the IS 250 utterly transformed my mood. The new petrol motor is as smooth as any V6 I’ve driven, and delivers high-quality performance through the excellent six-speed manual or automatic transmissions. And it’s more than just a svelte performance — its yowling engine makes you want to seek out those roads where its handling is able to shine, too.

Settle reckons this petrol Lexus is going to surprise a diesel-worshipping market and, despite its slightly inferior economy and emissions, I reckon he’s right. It’s a car I can recommend wholeheartedly, for it goes and feels like a Lexus should and is a worthy rival for a BMW 3-series.

The same cannot be said for the diesel. I mean, can you see a bunch of sharp-suited spooks pulling up outside the MI5 building in a rattling diesel, even if it is called a Lexus? Me neither.

VITAL STATISTICS

Model Lexus IS 220d
Engine type 2231cc, four cylinders
Power/Torque 175bhp @ 3600rpm / 295 lb ft @ 2000rpm
Transmission Six-speed manual
Fuel/CO2 44.8mpg (combined cycle) / 168g/km
Performance 0-62mph: 8.9 sec / Top speed: 134mph
Price About £22,400
Verdict A good effort spoilt by an unsuitable engine
Rating 3/5

THE OPPOSITION

Model BMW 320d £23,225
For As good a candidate for best car on sale as you’ll find
Against A dull and disappointing exterior

Model Honda Accord 2.2 i-CTDi £19,100
For Good looks, solid engineering
Against Lacks the cachet of the premium German brands