The new Rolls-Royce Droptail has an AP Royal Oak as its dashboard clock

Car companies and watchmakers have enjoyed a long and successful relationship. But while this usually involves a special edition watch styled to look like a certain car, this time Rolls-Royce and Audemars Piguet have taken things a step further.

The first of just four Droptails to be produced, Rolls-Royce’s latest car features an AP Royal Oak as its dashboard clock. Revealed to its owner at a private event during Monterey Car Week in California, the first Droptail commission is called La Rose, owing to its colour. The thousands of hours of coachworking put into creating the car is rumoured to have cost around $30m (£23m).

For that, the lucky buyer gets a two-seat convertible powered by the company’s well-known 6.7-liter V12 engine. The exterior paint, which took 150 iterations to perfect, and matching interior are inspired by the Black Baccara rose, a velvet-like flower that originates in France and is a favourite of the mother of the unnamed person who commissioned the car.

The interior is when things truly step up a gear. The dashboard is made from 1,603 Black Sycamore wood veneer triangles, creating an abstract impression of falling rose petals that took almost two years to create.

“Each triangle is cut, sanded and precisely positioned by hand, Rolls-Royce said, adding: “The pieces that appear to be stained light and dark grey are in fact presented in their natural hue; the colour difference is achieved by using veneer from several logs with different ‘figures’ – the natural pattern on the veneer.”

And so to the watch. Because the digital readout of other cars, or even Rolls-Royce’s standard analogue dial, simply wouldn’t do, the Droptail features a one-off Audemars Piguet 43mm Royal Oak Split-Seconds Chronograph GMT Large Date. It is powered by an automatic Calibre 4407 movement with a flyback chronograph and a split-seconds mechanism. Designed to match the car’s colourway, the AP has red counters and a red inner bezel, contrasting neatly with the block ‘openworked’ dial with rhodium-toned bevels.

Rolls-Royce says how fitting the watch wasn’t easy. “Integrating the timepiece presented a significant challenge: the clients requested that it should both be mounted in the motor car and also be removable, so that it can be attached to a strap and worn. This was realised with a powered clasp mechanism that gently presents the timepiece at the touch of a button.”

Once the watch is removed, the space left behind is covered with a titanium watch case, shown above, with a white and rose gold engraving of a rose instead of a dial; this motif is also found on the car’s Bespoke Audio speakers. The watch strap and blank head are stored in a leather pouch in the door when the watch is installed in the dashboard.