Just last week, we got our first look at the new BMW M4 Coupe in prototype form. Now, our spies have caught another prototype of the regular next-generation BMW 4 Series Coupe undergoing testing with less camouflage than before. The heavy camouflage has dropped, with just thin foil hiding the 4 Series Coupe's sleek design lines and details.

The kidney grille is still covered up, but our spies went in for a closer look. On closer inspection, we can see that the new 4 Series will have much larger nostrils inspired by the polarizing BMW Concept 4 unveiled at the 2019 Frankfurt Auto Show back in September.

This design decision is going to be divisive, but BMW wants the new 4 Series, M3, and M4 to have bolder designs than the 3 Series. Compared to the 3 Series, the new 4 Series will have a more aggressive design with narrower headlights and taillights and a lower roofline.

Don't expect any radical changes inside, however. In contrast to the exterior, previous spy shots have shown the cabin will look nearly identical to the 3 Series, with the same central 8.8-inch touchscreen, digital gauge cluster, and a center console with rotary controls to control BMW's iDrive system. Under the hood, the new BMW 4 Series will share the same engine as the 3 Series, which means the 430i will be powered by a 2.0-liter turbocharged four-cylinder producing 255 horsepower and the M440i will use a 3.0-liter turbocharged inline-six with 380 hp.

If you want more power, the new M4 is expected to use a 3.0-liter twin-turbo inline-six producing 473 hp, which will be sent exclusively to the rear wheels in the base model. The range-topping Competition model, on the other hand, will increase the output to 503 hp and feature an all-wheel-drive system that can be switched to rear-wheel drive at the push of a button in the M5. Purists will be happy to know that the new M3 and M4 will still be offered with a manual transmission, but only the base version will likely have this option.

The new BMW M3 and M4 aren't expected to enter production until late 2020 and launch in early 2021, so the new 4 Series should break cover in the second half of 2020.