The 2021 BMW M5 CS was the swansong for the F90 generation, and it was the wildest card in the pack, providing customers with a four-door sedan that could compete against proper sports cars, and beat them.

Almost forty years have passed since BMW introduced the first generation of the 5 Series in 1972, and the German automaker has improved this lineup constantly. However, the M5 F90 was the first to get not one but two upgrades over its short production run. So, while the M5 was for those who wanted a luxurious, go-fast car and the M5 Competition was for those craving a go-fast elegant vehicle, the 2021 M5 CS was for those who really wanted a four-door, four-seat vehicle that could breach into the supercar territory thanks to its performance. But the M5 CS was not just about power. It provided just ten ponies more than the M5 Competition. It was about look, suspension, weight reduction, and exclusivity.

At the front, the M5 CS instantly grabbed attention thanks to its golden rim of the kidney grille and the yellowish L-shaped daytime running lights. These were specific for the CS and unavailable for the rest of the range. Furthermore, this special version came standard with laser headlights. At the same time, the lower bumper sported a new design for the side scoops, while a honeycomb mesh adorned the lower air intake. As a last detail, BMW installed a carbon fiber lip spoiler under the apron. The M5 CS also boasted a carbon fiber hood fitted with vents that helped to cool the engine.

The car sat lower to the ground from its profile than the regular M5 and featured unique-looking gold alloy wheels. Furthermore, the door mirror caps were made from carbon fiber as well. Through them, bystanders could see the 400 mm (15.7-inch) carbon ceramic brake discs fitted with six-piston gold or red caliper, depending on the option. The car sat lower to the ground than the M5 Competition, and it featured a suspension carried over from the BMW M8. Finally, at the back, the automaker placed a carbon fiber spoiler on the trunk’s lid. The same lightweight material was used to create the diffuser that was placed under the bumper.

Inside, the automaker installed four sports seats. Those from the front were separated by the narrow center console that housed the iDrive controller and the onboard computer. Fronting the driver was a fully digital instrument panel, while atop the center stack was a touchscreen for the infotainment system. Out back, the M5 CS provided enough legroom and headroom for two adults, but the middle row was deleted. To make the car lighter, BMW installed a carbon fiber roof, so a panoramic glass or a sunroof was out of the question. Additional carbon fiber trims and Alcantara decorations adorned the vehicle’s interior.

Under its skin, the M5 CS concealed the suspension carried over from the M8 GT vehicle, which made it more planted to the road. The engine was the same 4.4-liter V8 as the rest of the M5 siblings, albeit it developed 635 PS (626 hp). BMW paired it with an eight-speed automatic transmission that sent the power in all corners.