It's clear from the styling of the XF and XJ saloons that design chief Ian Callum has been developing and evolving a new design vocabulary for Jaguar that, while it may make an occasional nod to the marque's enviable heritage, looks decisively towards the future. Whilst the two saloons have been well received in terms of value, technology and comfort, there's been a nagging doubt about the coherence of their design. They are not "good-looking" cars. In addition the whole range, including the bonkers-fast and sporty XK, is still seen as older person's transportation. Well, no more. This week Jaguar has delivered a stunning and beautiful "pure" sports car concept that aims to give the mighty Porsche 911 a run for its money.