There was a time when cars stayed in their individual pigeonholes. A luxury car was exactly that, with no real sporting pretensions. A sports car, meanwhile, would be quick, but cramped, uncomfortable progress for the price of speed would be expected. Then came the M5.

There have, of course, been other fast four-door cars. A standout was the classic 1960s Q-car – a high-performance vehicle with a modest exterior – the Mercedes 300 SEL 6.3. Yet none have had the enduring appeal and lineage of the BMW M5. The M5 was avaricious. It wanted it all. Four doors – tick; sports car handling – tick; supercar performance stats – tick. There was also, certainly in the early models, a clear case of the wolf in sheep’s clothing. The fact that you had  something that only those in the know, knew you could discharge. A concealed weapon if you will. A red Ferrari was of course fast, but a grey four-door BMW saloon, not obviously so. The thrill of being able to unleash this almighty power by surprise was seductive to many buyers. I’ve always thought there was something a bit James Bond about this approach… despite the car being German and not an Aston Martin. It had the sense that it could deploy a massive amount of grunt and ability and then dust down the grey suit and straighten the tie before pulling up in front of a hotel in an unassuming manner.

“As is custom, it has an incredibly sophisticated interior for a demonically fast vehicle”

BMW’s first generation car broke cover in 1984. There had been ‘M’ (for ‘Motorsport’) badged 5 Series cars before, such as the M535i, yet this was a big step forward and went by the simple moniker of M5. The performance figures wouldn’t set the world alight by today’s standards, but to put it into perspective, it had more horsepower than its contemporary Magnum-moustachioed Ferrari 308. It was hand-built and used an engine developed from impeccable stock, the 24-valve straight six that powered the M1 supercar of the 1970s. It was available with or without the M-Technic body kit. Without it, the car really could be confused for a bog standard 518i… but of course, that was, for many, part of the charm. This unassuming vehicle was a supercar masquerading as a run-of-the-mill executive saloon… and this was no ‘stick a big engine in’ blunt instrument, this was a finely-tuned weapon. Later models started to look a little more muscular. A brute in a suit that had less of the elegantly understated demeanour of the first car that exercised such extreme discretion, but sales would grow and grow.

The E34, the second-generation M5 was the first to offer the ‘Touring’ body or estate car as we know it. There was something even more stealth about having a car that looks like it could deliver a wardrobe and still embarrass a peacocking sports car. By the third evolution, the car had simply become too popular to be hand-built and added a sexy V8 engine into the mix. The fourth generation was, for many, peak bonkers with its howling F1-inspired V10 engine, a beefy seven-speed sequential gearbox and visually  important 200mph speedometer for the kids to press their faces against the window and go ‘Wow!’

The F10, fifth-gen car, was the first with forced induction – turbo – and continues the custom of each new model pushing the boundaries of innovation while retaining the same purpose. And so it goes on and on. Refine and repeat. Which brings us to the new 2018 car that has, for the first time, four-wheel drive – cue howls of derision from the die-hards. Yet let’s remember we now have twice the power of the original model and all the bravery in the world will not help anyone but the most skilled of drivers to handle 600 bhp through the rear tyres alone. You can actually switch off the system and take it back to pure rear wheel drive only, but this should come with a warning, or at least a little voice that asks, ‘Are you sure… really, really sure?’

This is a very accomplished all-round car. As is custom, it has an incredibly sophisticated interior for a demonically fast vehicle – classical music inside while all is furious heavy metal on the outside. Carbon ceramic brakes are an option with natty gold callipers and the obligatory M logo. BMW will tell you they have improved thermal stability and less fade, but all you really need to know is they will stop you very quickly. A carbon-fibre roof is another first and helps shed some more pounds off what is a big car.

So now into its 6th model cycle, the BMW M5 is over 30 years old and can rightly claim to be the father of the executive express.

bmw.co.uk