Mercedes unveiled the new AMG-developed SL Roadster at the end of October 2021 and we didn’t have to wait a long time to see its coupe sibling. The version with a fixed metal roof was caught testing out in the cold last week, and now our spies are back with more interesting spy shots. While the first prototype was likely a six-cylinder version judging by the round exhaust tips, today we're dealing with a V8 model.

A quick look at the back reveals the angular quad exhausts we've seen already on the new SL with its twin-turbo V8. The 4.0-litre engine makes 476 bhp (350 kilowatts) in the "55" model and 585 bhp (430 kW) in the flagship "S63." We're expecting identical figures for the next-generation AMG GT Coupe. However, the three-pointed star could decide to spice up the coupe later in its life cycle, culminating with a new Black Series.

Gallery: 2023 Mercedes-AMG GT Coupe 55 / 63 sy photos

The prototype caught in northern Europe has chunky brakes with gold callipers to mirror what official images of the SL 63 are showing. Despite carrying a lot of camouflage, the new coupe already gives us the impression it looks sleeker than the model it's about to replace. Logic tells us it will be lighter by dropping the bulky folding roof mechanism and possibly deleting the roadster's cramped rear seats.

While the SL will cater to customers looking for a posh grand tourer, the Coupe will be the sportier of the two versions. Consequently, AMG will do more than just replace the roof and (maybe) delete the back seats before calling it a day. For the first time ever, the iconic roadster gets all-wheel drive, so we're eager to see whether the Coupe will also carry the 4Matic badge. Sticking with RWD would make it even lighter than the cabrio.

The official reveal is likely scheduled to take place before the end of 2022. Mirroring the SL, AMG could prioritise the V8 versions first before adding a base six-cylinder model. There are also rumours of a spicy range topper dubbed "GT 63 S E Performance" with well over 800 bhp in the same vein as the AMG GT 4-Door Coupe plug-in hybrid. That said, we're not so sure the engineers will be able to cram the PHEV setup in a considerably smaller car.