As everyone continues to wait with bated breath for the respective debuts of the Speedtail and 720S Convertible, another McLaren is brewing in the shadows. There are no definite details yet, but numerous rumors hint that McLaren’s MSO division is preparing a mysterious new supercar that’s tentatively called the BC-03. It is also believed that the BC-03 will draw inspiration from McLaren’s Ultimate Vision Gran Turismo Concept and that only five units are planned.

Rumors of a new McLaren supercar aren’t entirely new for the British automakers. In fact, a lot of the limited edition supercars it’s released started out as rumors. The Super Car Blog, for instance, was the first to report that the BC-03’s design would borrow cues from the McLaren Ultimate Vision Gran Turismo Concept that became available for Grand Turismo Sport back in October.

Back then, nobody thought of the Ultimate Vision Gran Turismo Concept as a potential precursor to a limited edition production supercar, and yet, here we are, a little over a year to the day the concept first appeared, it’s back in the news as a potential blueprint for a limited production supercar.

Details are still scarce at this point, but Instagram user dan_am_i added more weight to the rumors by posting a photo of what appears to be a private product unveiling that Mclaren hosted for its most loyal of customers. The photo reads, clear as day, “MSO-Bespoke Commission BC03.” There’s no follow-up to the post, though it’s not like there needs to be one at this stage of the car’s supposed development.

Whatever it is that McLaren’s planning, it’s apparent that it’s not going to fall into any one of the automaker’s series of models. It could fall under the Ultimate Series, but only five units are reportedly planned, so that’s something worth keeping an eye on. Regardless of where it’s classified or what it’s going to look like — a user from the McLaren Life forum hinted that the BC-03 would use a new, cutting-edge type of carbon fiber — it appears that McLaren has its hands full on more than just the Speedtail and the 720S Convertible.

For now, though, the rumored super/hypercar can still be classified as rumor until we get official word from McLaren that its MSO division is actually working on one.

Further reading

Read our full review on the 2019 McLaren Speedtail.

Read our full review on the 2017 McLaren Ultimate Vision Gran Turismo Concept.

Read our full review on the 2018 McLaren 720S.