The tag on the key chain says, “Mr. Qvale”, the script carefully laid out in looping ballpoint pen. At one time, these keys hung on the hook in some paper-strewn California office, while nearby in a garage men hammered on MGBs and Morgans and the like. Norwegian-born Kjelle Qvale was an importer of such things, and while sports car culture in the US might have spontaneously developed without him, there's little doubt of the influence he had.

He was the first distributor of Jaguar on the West Coast. He was a founding member of Pebble Beach Concours D’Elegance. He is credited with designing the legendary Corkscrew at Laguna Seca. And when he drove, he sometimes took his own Jensen Interceptor.

Interceptor. As a name for a car, is there any better? Perhaps the Plymouth Fury, but besides that, there's nothing more menacing-sounding than the fighter-bomber appellation given to this British-American hybrid.

The Interceptor was bodied by Italian design house Carrozzeria Touring, who previously bodied such lithe grand tourers as the Aston Martin DB4 and the Lamborghini 350GT. Assembly was performed in the British Midlands, home to Morgan and MG et al. These are, you might think, the ingredients for some superleggera European confection of speed.

However, the Interceptor is more like an F-4 Phantom than a balletic Spitfire. Under that long nose is a massive Chrysler-sourced 440ci (7.2L) V8, producing around 255 hp in stock trim and enough torque to re-orient Greenwich Mean Time about a half-hour in either direction. It's part muscle car, part genteel English-Italian grand tourer: a gentleman who knows how to box, and not just by the Marquess de Queensbury rules.

This is the last such car to roll out of the factory before the bailiffs showed up and the company went into receivership. Actually, according to rumour, this car was actually pushed out of the West Bromich factory after the bailiffs arrived, when Qvale claimed it as his personal car. The doors were padlocked behind it, and while other cars were later assembled from the half-finished shells and spare parts remaining in the factory, this was the last true Interceptor made.

The story of Jensen is just as interesting as that of Qvale himself. Founded by a pair of brothers in the period between WWI and WWII, the company made a name for itself making small sports-car bodies on existing chassis, and later building commercial trucks. During the Second World War, the company focused on making war materiel like tank turrets and heavy trucks like ambulances and fire engines.

After the war, demand for sportier cars resumed, and the first Interceptor was born. Designed by Eric Neale, this coupe and convertible was based on the Austin A70, and offered sprightly performance. Neale's later work, the fibreglass-bodied 541R and then CV8, set the groundwork for the later Interceptor, with the latter ditching its English-sourced straight-six for a Chrysler V8.

Aside from producing their own cars, Jensen also took in a great deal of contract work from outside. Most famously, they built the bodies for the great-looking Volvo P1800 and were involved in the development and production of the V8-powered Triumph Tiger.

Perhaps it was this pan-European fingers-in-every-pie business model that gave rise to the parentage of the next Interceptor, but whatever the reason, the replacement for the CV8 would have its roots in multiple countries. Italian coachbuilders Touring designed the original body, with Neale making some key subtle changes for production. The engines came from Chrysler, starting with a 383ci (6.2L) V8 coupled to a Torqueflite automatic transmission and ending up with the mighty 440ci (7.2L) V8.

Power would wax and wane depending on emissions requirements over the life of the Interceptor, but all would come with that characteristic Mopar rumble and plenty of poke. The earliest ones are probably the best, coming as they did with underrated engines – most 383s were supposed to have around 325 hp and the 1971-only six-barrel 440i as much as 350 hp, but these are very conservative figures. Further, because the Interceptor had all-American running gear, it was just as tunable as your average heavy-hitter Chrysler. One even shows up in the Fast & Furious franchise, all hot-rodded to hell and with a primer-grey paint job.

The one we drove, a rare coupe version, lacks the characteristic bubble-backed silhouette so well-loved by anyone familiar with the Interceptor. It's entirely factory-spec, and as it left the place in May of 1976, that means a single carburetor atop the 440ci V8 – this is no ground-pounding stoplight racer, but a genteel grand tourer. Its paint is a sumptuous brown, its carpets deeply piled, and the walnut dash richly polished. I take the keys marked Mr. Qvale, fit them in the ignition, and fire up the V8.

Several variants of the Interceptor were made, the most common being the fastback. A few coupes were built, and the rarest of all is the convertible version. Also available was the FF, so named for Harry Ferguson's at-the-time revolutionary four-wheel-drive system. A manual transmission was available, but is exceedingly rare.

As it glides along the backroads of Washington State, the Interceptor's real surprise is in how small it feels. Most American cars of this period feel huge on the road, ponderous of heft and slow to change direction. If they've had their V8s breathed on, there's often plenty of Go under the hood, but Stop and Turn are usually lesser priorities. Alarmingly so.

The Interceptor, on the other hand, drives with a certain modernity to it. You could see hitting the California interstates in this car, at a time before they became clogged with so much traffic, then hopping off for a cruise down the coast, that big V8 thumping away happily under the car's long hood.

It's relaxing, and because this one's been so thoroughly overhauled, there's little chance it's going to break and strand us by the side of the road. Like all British Midlands–built cars of the 1970s, the Interceptor suffered from an oft-disgruntled workforce, and occasionally indifferent build quality.

However, this car, found as a near-wreck in a garage not far from Qvale's British Motor Car Distributor offices, has been fully resurrected by Doug Meyer, a self-taught Interceptor restorer who's worked on more than a dozen restorations. Now retired, he can take more than a year to bring each car up to a condition far above that in which left the factory, at a cost that often creeps into the six-figure range. Jensen Interceptors aren't that collectible yet, so these are often labours of love for people with deep pockets who see the car with affection, not as an investment.

Qvale's Interceptor was just such a project for Meyer, and it involved a hideous amount of research. In order to get things correct to factory spec, he often had to order two and three cars’ worth of materials, everything from badges to sheepskin covers for the seats.

But the result is something of a V8-powered time machine, glittering in the sun as it rumbles down a leaf-strewn lane. Jensen's woes in the 1970s led to Qvale becoming chairman of the company, but even he couldn't turn the ship around. After it went bankrupt in 1976, several entities purchased the leftovers and tried to restart the operation; they were putting the paddles to a corpse. While the Interceptor has been dug up, time and again, with power coming from a Corvette V8 in one notable example, the car can't seem to get traction.

Perhaps it's best remembered as a product of its time, a machine that the world will remember, but not one it really needs to see again. The best of Italian, British, and American automaking, all hammered into one amalgam, given one of the best names a car ever had, and let loose on the world. Like Mr. Qvale, the Interceptor is a legend. Sometimes, though, legends belong in the past.

However, you can occasionally find an Interceptor of your own to revel in the glory of this short-lived brand.

We found a fetching example in Richmond Hill, Ontario: it's a 1975 model, making it nearly the last of breed.[And... it's gone! –Ed.] It's a Mark III, and would have been produced by the Bromwich factory under the auspices of Kjelle Qvale.

The fastback body with its bubble-shaped rear canopy is instantly recognizable to any fan of English-built classics. The Mopar rumble coming out of those twin tailpipes will turn the head of any muscle car fan, and the Brienz Blue paint job (said to be original) will please just about everyone.

This one is claimed to be essentially rust-free, and has been sitting in a garage for the last two years. Engine parts for an Interceptor aren't all that difficult to find thanks to the Chrysler connection, and if the chassis and body are sound, it's a compelling mix of new-world power and old-world style.