Here’s a treat for Range Rover enthusiasts, on the day that the amazing Mk4 is unveiled. This is the experimental V12-engined Mk2 Range Rover, originally intended to be launched in 1999 by then-owners BMW. It was, perhaps, the first attempt to exploit the Range Rover as a proper luxury model.

The brand’s various owners have considered the Range Rover’s potential as a full-on luxury car for over 20 years. Arguably, there had been great resistance to taking the car away from its rural roots. The original Range Rover remained relatively spartan and it took 15 years before the factory even built a five-door version.

By the late 1980s, however, Land Rover was beginning to understand the potential for Range Rover as luxury car. The second-generation model - the 38A - had a much more luxurious interior and it rode on air-suspension. But it was BMW (which bought Rover Group less than a year before the 38A was launched) who really wanted to push the car even further upmarket.

BMW’s engineering chief Wolfgang Reitzle wanted to see further improvements to the car’s interior and commissioned work on a version of the 38A fitted with a V12 BMW 7-series engine. The bigger engine demanded a much longer (around six inches) front overhang which could have compromised the car’s off-road ability. This exclusive picture shows the tightness of the fit.

Two running prototypes were built and this neat re-styling was also proposed. It was intended to partly disguise the front overhang and to distinguish the V12 from the V8 version. However, the project was dropped by BMW.

Reitzle’s attention turned to the BMW-engineered Mk3 Range Rover, a car which he thought could - with the right engine and trim - demand a six-figure showroom price. However, by the time it was launched in 2002, the Land Rover was under Ford ownership.

Reitzle returned for a short while to control his pet project as boss of Ford’s Premier Automotive Group but the momentum behind a super-luxury Range-Rover had waned in the post-9/11 world. Even so, there were rumours a version of the car using an Aston Martin V12 engine was considered and Reitzle was still convinced that a £100,000 Range Rover was a viable proposition.

Reitzle’s vision arrived 15 years after the first V12 prototypes. The huge boom in super-luxury branded goods - driven by China - convinced Land Rover to send the Mk4 in a new direction and, as a taster, produce a £120,000 super-luxury version of the Mk3 model. Called the Autobiography Ultimate Edition, it featured a teak-lined boot and bespoke rear cabin.

The 500-off production sold out rapidly, paving the way for the 2013 Range Rover 4 to finally shake the mud off its boots and repurpose itself - especially inside - as one of the most prestigious luxury cars on sale.