“There are AMG fans for whom our V12 biturbo engine is the measure of all things. For this clientele we have developed a unique car in the form of the new S65 AMG Coupé. The S65 AMG-fettled Coupé is the most expensive car in the Mercedes-Benz catalogue. Under its bonnet lurks a twin-turbo, 621bhp, 1000Nm, 6.0-litre V12 petrol engine. All big numbers, but none so big as the monetary jump between the £125,000 eight-cylinder S63 and the £183,000 twelve-cylinder S65.