McLaren never built an open-top version of its iconic P1 model. All 375 examples of the 903 hp hybrid were created as closed coupes. In 2013, when the P1 debuted, if you wanted to feel the wind in your hair at 200-plus mph, you had to buy a Porsche 918 Spyder, splurge for a Bugatti Veyron 16.4 Grand Sport, or wait three years for a Ferrari LaFerrari Aperta.

In 2022, though, British engineering specialist Lanzante transformed the flagship McLaren into the P1 Spider. Yet after the designer of the original P1’s exterior, Paul Howse, was called in to mastermind the complex makeover, just five cars were converted. Now, one of those super-rare P1 Spiders is headlining the Miami Auction presented by Bonhams on May 3.

“This is a unique and truly exceptional car,” touts Allan Greenfield, head of sale for Bonhams|Cars. “It’s the second of only five P1 Spiders ever built, has been driven less than 200 miles since the conversion, and shows fewer than 3,000 miles from new.”

Even before its Spider conversion, this P1—number 209 in the production run—was making headlines. Known as “the Professor,” it was originally sold through McLaren of Philadelphia, and was the only P1 painted a custom shade of metallic cobalt blue named “Professor 2 Blue,” after the original owner’s former job as a professor at Harvard Business School.

In addition to its unique paintwork, it was commissioned with specially molded carbon-fiber bucket seats trimmed in red leather with Ferrari 365 GTB/4 Daytona–style ribbed padding. At the request of the owner’s wife, a unique vanity mirror was designed for the passenger side and etched with the words “You look beautiful.”

On top of the P1’s roughly $1.15 million MSRP, the additional options from McLaren Special Operations totaled almost $140,000. After its completion, the P1 was signed by McLaren’s then-boss Ron Dennis and the marque’s design director at the time, Frank Stephenson.

“The Professor” was used by its enthusiast owner—a former venture capitalist before his stint in academia—for more than two years prior to being auctioned by Gooding & Company at its 2017 Amelia Island sale, where it sold for a record $2.39 million. The proceeds went to endow a teaching faculty chair at the owner’s former alma mater, the Rose-Hulman Institute of Technology in Terre Haute, Ind.

After five years of minimal use by its Ohio-based second steward, the P1 was one of the stars at an RM Sotheby’s auction in 2023, where it sold for $2.095 million. The car’s third and current owner subsequently contacted Lanzante—famous for its take on the P1 GT, P1 LM, and 1995 Le Mans–winning F1 GTR racer—to commission a roofless version after seeing the prototype’s debut at the Goodwood Festival of Speed the previous year. 

With the expertise of Howse, Lanzante was able to successfully remove McLaren’s carbon-fiber roof and create new carbon-fiber buttresses containing air intakes to feed the 3.8-liter V-8’s twin turbos. All the while, Lanzante’s engineers and carbon-fiber specialists managed to retain the formidable structural integrity of the P1’s MonoCage chassis. When the structural work was completed, this P1 Spider was painted in historic Gulf racing colors, and its interior was completely retrimmed in white, weather-resistant leather with orange seat piping and orange seat belts.

“With only 375 McLaren P1 coupes ever built, each one is prized by collectors the world over. But with just five P1 Spiders in existence, their collectability is unparalleled,” Greenfield tells Robb Report. “And this example, with its iconic color scheme, low mileage, and exceptional provenance, has to be the ultimate.” That sentiment is reflected in the fact that when it crosses the Bonhams auction block, during the weekend of Formula 1’s Miami Grand Prix, it’s expected to fetch anywhere from $4 million to $5 million.

Click here for more photos of this 2015 McLaren P1 Spider.