A 1926 Rolls-Royce Phantom I displaying a stunning baroque interior starred in Bonhams' Bond Street Sale on December 4.
It realised £561,500 ($656,833).
It's known as The Phantom of Love, as Woolworths executive Clarence Gasque commissioned it as a gift for his wife.
The inside was designed by Charles Clark, a Wolverhampton-based interiors specialist. The inspiration came from a sedan chair made for Marie Antoinette.
No expense was spared, with the tapestries on the seats handmade in France and the cherubs on the ceiling painstakingly painted on.
The entire car took around 10 months to complete, at a cost of around £6,500 ($7,999) - an astronomical sum at the time.
Rob Hubbard, Bonhams' senior car specialist, told the Telegraph newspaper: "It is probably the most expensive Rolls-Royce ever made…
"Inside, the rear of the car is a work of art and a piece of history. It is like stepping inside a very fine Georgian manor house."
A 1914 Vauxhall 25HP "Prince Henry" sports torpedo realised £516,700 ($657,087).
The lot is considered the world's first sports car, capable of speeds up to 80mph.
It was created by engineer and car designer Laurence Pomeroy and later owned by his son, Laurence Pomeroy Jr.
James Knight of Bonhams told BBC News: "The car is incredibly rare.
"In comparison to what else was out there, this car was absolutely the supercar of its day."