The next-generation Bentley Flying Spur is close to being completely unveiled, but the Crewe-based company is not without a few tricks up its sleeves. Seen here is quite possibly a plug-in hybrid version of the opulent four-door saloon, with the giveaway being the additional “fuel cap” on the rear left side of the car.

The position of the “fuel cap” is quite unorthodox, because as far as Bentleys go, the lid is often seamlessly integrated into the upper haunch of the vehicle, particularly on the right side for the Flying Spur. The charging port on the new Bentayga Hybrid is also on the left, adding further weight to this speculation.

Now, there’s no way of telling what’s lurking under the bonnet of this test mule, but word is it will share the same 3.0 litre plug-in hybrid V6 from the Bentayga Hybrid. Again, no performance figures have been revealed at this point, but the same system in the Panamera E-hybrid produces a total system output of 456 hp and 700 Nm of torque. Expect the Flying Spur to match those figures, at the very least.

However, given its MSB roots (the Flying Spur shares the same underpinnings as the Panamera), the 4.0 litre twin-turbo V8 from the top-of-the-line Panamera Turbo S E-Hybrid may also be featured in the Bentley. There, the plug-in powertrain makes 680 hp and a whopping 850 Nm of torque, enough for it to sprint from 0-100 km/h in 3.4 seconds and a top speed of 310 km/h.

The Flying Spur will ride on a lengthened MSB-F platform that’s commissioned for rear-wheel drive and all-wheel drive applications, and it will be used for the Volkswagen Group’s luxury sports saloon. Expect a host of electronic technologies, weight reduction and autonomous driving systems to go with the architecture. The Flying Spur is slated to debut later this year or early 2019.