That is so close to the truth I am going to let you have the point for that. It is indeed the wife of said Joseph Mackle, both London socialites. It was actually purpose built to win concours d'elegances with - which was a serious business at a time where Daimler was not making a mark there.
Daimler put the chassis at the disposal of their main London dealer Stratton-Instone for free, who had this body built by Hoyal (not one of the big 'names'), quickly and for very little money. Though the car itself was a success, and in this sense was the predessesor of the special low chassis Daimler Double Sixes of the years following, which are now winning the big American concourses, this car -as far as I know - has disappeared without trace. Daimler failed to make its mark as a fashionable car, partly also because they had not much of a reputation on the mainland of Europe, partly because the suspension seemed to particualry unsuitable for European roads. (Many of their customers in the U.K. also had a Rolls-Royce which they particualry would use for fast driving on the 'Continent'.) Another ill fated attempt was made by the Dockers (who ran Daimler in the late forties and early fifties) to achieve the same sort of glamour Rolls-Royce, French, German and Italian top cars did have, again to fail miserably, but at that time alienating their traditional Royal and country gentry customer base with the vulgar approach chosen.