Just about everyone knows weight is the enemy of performance, including BMW. It developed the M5 CS by shaving off a considerable 70 kilograms (154 pounds), but it's still a heavy car. The super sedan weighs 1,825 kg (4,023 lbs), and there's a pretty good chance the next-gen model will be fatter given its PHEV powertrain. The engineers could throw in more carbon fiber, but that would drive up the price furthermore.

It's not all bad as the electric motor will increase total output while the battery pack should significantly impact efficiency. So much so the new BMW M5 could offer an all-electric range. This is not a wild assumption on our part since the AMG E63 rival is expected to inherit the PHEV setup from the Concept XM, which promised 50 miles (80 kilometers) without sipping gasoline.

Before its probable debut in 2023, the revamped M5 has been caught in northern Europe carrying the production body. However, it's missing the final lights while the exterior is cleverly camouflaged with extra layers of disguise held in place using rivets. As if the "Hybrid" stickers on the front doors and rear bumper weren't obvious enough, the prototype flaunts the cap for the charging port in the front-left fender.

Gallery: 2024 BMW M5 new spy photos

You can easily tell it's the full-fat M model by the sheer size of the brakes, and we're not just talking about the front ones as the rear discs are also pretty chunky. At the back, the quad exhaust is a typical M trait, albeit that will change in the near future. Why? Because M Performance models will adopt the more aggressive look as well, starting in 2023 with the X1 M35i.

Thankfully, the next 5 Series / M5 won't get the hugely controversial kidney grille design seen on some recent BMWs. It will borrow the flush door handles installed on newer models, while the rear seems a tad shorter with a more angled trunk lid. We're getting the impression the side skirts are larger, maybe because the battery pack is mounted between the axles for better weight distribution.

Aside from electrifying the M5, BMW will actually be taking out the combustion engine altogether by introducing the i5. The EV model should arrive next year together with the conventionally powered 5 Series, with the range topper earmarked for a 2024 launch.

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