Dennis Flather was a wealthy Sheffield steel merchant who's first special was a Marwyn fitted with a Scott engine (MARwyn scOTT) and some fairly ungainly bodywork in 1948. The Marwyn was perhaps not the best starting point and the Scott rather less powerful than a JAP so performance was poor, Dennis failing to finish the Grand Prix race at Silverstone in October and again in May 1949 and at Blandford in August.
For 1950, he replaced much of the body with a somewhat sleeker one and fitted a Vincent Grey Flash, renaming the car the Blue Flash, but this failed to substantially improve things. He did take a ninth place at Goodwood at Easter and tenth at Prescott in May.
For 1951, Dennis switched to the Flather Steel Special, an all new car, more like a Cooper Mk V but with greater ground clearance.
Please get in touch if you can tell us more of Dennis or any of his cars.