The thing with Steve McQueen is this: if you go into an empty bathroom, turn off the lights, and say Steve McQueen’s name three times fast, McQueen’s ghost will appear in the mirror; then, your car instantly triples in value.

Call it the “McQueen Effect.”

Call it that because McQueen owned so many damn cars. Call it that because all the cars he owned were eminently desirable, cars that have all seemingly tripled in value since his death. Call it that because people still worship at the McQueen altar today — and the unholy combination of the three elements makes for good auctioneering.

Keep in mind the 275 GTB/4 NART Spider from The Thomas Crown Affair that destroyed, pulverized, obliterated the auction record for road-going cars last year: $27 million. McQueen had one, of course. Imagine how much his NART Spider would go for if famed New York collector Anthony Wang ever parts with it.

In 1963 McQueen bought his first Ferrari, a brand new 250 GT Lusso, brown on chocolately brown, fitting for the man of supreme taste that he was. Many road trips with wife Neile followed, up until “a constant irritation developed…” (said Greg Duckloe in RM Auctions Magazine) “…concerning its propensity for burning oil and smoking under hard acceleration.” He sold it in 1967 for the newest Ferrari yet, the 275 GTB NART Spider — blue on black, slightly customized by his friend Lee Brown with an aggressive rear spoiler and a flip-up fuel cap. McQueen fell in love. He loved cruising around Los Angeles in those first days of ownership — loved the top-down feel, loved the power and honeyed sound from the 3.3-liter V12 — right up to the part where he nearly wrecked it.

Steve McQueen's Ferrari is up for auction in August. Blake Z. Rong/Autoweek

McQueen had been cruising down the Pacific Coast Highway when a pair of guys in a truck, their attentions turned toward some ladies, drove into the back of him. (Some say he crashed first, into the car in front; some say he was rear-ended. All we know is, those ladies probably didn’t escape his attention either.) The car was nearly totaled, hit with such force that both doors bent outward. McQueen parked it at a gas station in the Pacific Palisades, then promptly ordered another one — a 1967 Ferrari 275 GTB/4 coupe, delivered to Hollywood Sports Cars, John von Neumann’s dealer to the stars.

As with his Jaguar, McQueen had a knack of winding up with cars in colors he didn’t like. In this case, the car was delivered to Neumann in an airy shade of Nocciola, Ferrari parlance for metallic gold — a shade resembling toddler effluvia that barely worthy of Brown Car Appreciation. Brown, who prepared most of McQueen’s cars (including the ones used in Bullitt) painted it a subtler Chianti Red. It’s not the straight-up Ferrari red but it is instead deep and luscious, capable of changing its mood from dark red to a classic brightness; coincidentally, it also pops up on a few Volkswagen buses. The driver’s side mirror was streamlined, a retractable radio antenna added, Borrani wheels from his NART installed — the GTB/4 was the first Ferrari to swear off wire wheels — and seats reupholstered by Tony Nancy, who had done the same for the Jaguar XKSS.

McQueen sold both of his Ferrari 275s in 1971, right before he made Le Mans, pledging allegiance to the Porsche. We were at the mega-cool office and showroom of RM Auctions, in Culver City, Calif., with its exposed beams, heavy midcentury desks, a bomb hanging from the ceiling, when we heard a story about this: right after McQueen got back his newly-repaired NART Spider, he drove it to the studio and the security guard said, “how’re you doing, Steve? Why, that’s a nice Jaguar you got there!”

“ No other person defined, and was defined by, the cars he owned as much as McQueen. ”

We don’t know if that’s true. McQueen, of course, had no objections to Jaguar ownership. Regardless, both Ferraris were gone by the end of the year. The NART went quietly to a California collector, but the coupe sold to fellow actor Guy Williams, who famously played Zorro in the television series.

It changed hands a couple of more times after that, and along the way some ignominious fool, envious of McQueen’s blue Spider, perhaps, cut the roof off in a NART conversion. This happened sometime in the 1980s, of course; there was no accounting for the tornado of questionable taste which defined that decade.

The car eventually found its way into the hands of a famous race car driver who prefers to remain anonymous. Mister Anonymous Race Car Driver took it to Ferrari in 2010 for a full restoration, and the Classiche department, paint at the ready, certificates of authenticity in hand, finally put the roof back.

The 275 GTB/4 is much smaller than you think; the photos make it look larger than life. It’s so low to the ground it’s a vacuum cleaner, a curvaceous little thing, but just one big curve stretched taut across its flanks. Compared with the earlier 250s the 275 is a little pudgy, but it still evokes a maturity in its long, subtle lines. Sergio Pininfarina claimed that his designers turned to the 250 GTO for inspiration, and the haunches and tail speak volumes about that.

The /4 is what makes this car special: four cams for the high-strung 3.3-liter V12, six Weber carburetors, a dry sump that necessitated 17 quarts of oil. Pininfarina redesigned the body to match this new engine. Three hundred horsepower, nearly 100 per liter. “I swear,” said Jason Barlow of Top Gear, “you can feel every single one of them saddling up and charging off.” The Lamborghini Miura could do 170 mph, but the classically-styled 275 could hit 160 mph. Who needed to win the top speed war, anyway? In 1965, Autosport deemed it “close to perfection.” Road and Track called it “the most satisfying sports car in the world.”

By all accounts, it even handled pretty well. One contemporary review: “Hit the tightest horseshoe corner at a decent lick and it can become hard work to keep that long nose tucked in but, as the car starts to wash away across the track, you can bring it back into line using the responsive foot-long — but barely more than an inch wide — organ throttle. Just be careful not to hit a bump mid-corner or it really will spit you out.”

Earlier this year, a 275 GTB/4 sold at Bonhams for a record: $3 million, the highest anyone’s ever paid for such a car. The mind reels at the billions of kajillions of dollars that a McQueen-owned car will sell: RM Auctions believes that it’ll go for $9 million at least. “It’s a joker car,” said an automotive consultant, who then examined the door frames gaps before finally concluding, “But you know, it’s McQueen.” The collectors gathered were a tightknit circle of compatriots who picked and chose at a rational level; only they could decide whether they had enough McQueen dedication in their veins. “ I don’t go for provenance of a car,” said Dr. Peter Fodor, whose relatively new five years in the collecting world goes all the way back with RM Auctions. (In the next room was his Ferrari 330 GTC set to be auctioned soon.) “It would be interesting for a lot of people. It’s beautiful, and I know the guys who restored it.”

Peter Sellers owned a 275 GTB. So did Miles Davis, and Clint Eastwood, and the Shah of Iran (And Nicholas Cage, if we want to clutch at straws.) But no other person defined, and was defined by, the cars he owned as much as McQueen. And until the King of Cool abdicates his spiritual throne, there can be only nowhere for his cars to go but up. Sometimes, the McQueen cachet manifests itself in utter ridiculousness: in 2011 his 1970 Porsche 911S sold for $1.375 million, more than eight times the price of an already sky-high Porsche.

Of course, that car also wound its way into the Le Mans flick.

This Ferrari never made it into a movie, unlike the $27 million NART Spider, but McQueen did warm its seats for five years. It also had its roof hacked off at one point, then reinstalled: potential deal-breakers otherwise, but it’s not like they’re making many 275s anymore. A 1967 Ferrari 275 GTB/4 is supremely desirable to begin with — but if there’s one option that can never be factory-installed, it’s celebrity provenance.

RM’s Monterey auction begins Aug. 15, to coincide with the Pebble Beach Concours d”Elegance.