Prototypes for Mercedes-Benz’s next-generation S-Class have been spotted again.

The car is expected to be revealed in early 2020 and should be available later that year as a 2021 model.

From earlier test mules, we know the size and proportions will match up with the current model but there will be a slightly wider track, and it also looks like the hood will be lower and longer. This should give it an impressive stance.

2021 Mercedes-Benz S-Class spy video from Motor Authority on Vimeo.

The current Mercedes-Benz S-Class, the W222, was introduced for 2014 and immediately rocketed to the top of the sales chart. The six-figure sedan racked up more than 100,000 sales in its first year and that was before the arrival of additional body styles such as the two-door cars and extra-long Maybach and Pullman.

It’s clear the new S-Class has some big shoes to fill. Luckily for it, it will adopt a new platform, in this case Mercedes’ MRA design for rear-wheel-drive cars. The current S-Class rides on an updated version of its predecessor’s architecture.

Every powertrain will be electrified, either with mild-hybrid or plug-in hybrid technology, and most engines will either be a 3.0-liter inline-6 or 4.0-liter V-8. There won't be a battery-electric version as Mercedes plans to launch the EQS to cater to EV fans. The EQS, previewed at the 2019 Frankfurt International Motor Show by the Vision EQS concept car, is also expected for the 2021 model year.

Mercedes-Benz Vision EQS concept

Mercedes-Benz Vision EQS concept

But getting back to the new S-Class, there will be much more advanced self-driving systems, including perhaps a Level 3 system. This is where the car can handle its own in certain situations, leaving the driver free to do other things. However, the driver will need to be ready to take back control at a moment's notice.

Inside, the dash will still consist of a dual-screen setup, but the secondary screen will increase dramatically in size and be mounted in a portrait orientation. At the bottom of the massive screen will sit a row of buttons, with the rest of the controls relegated to the touchscreen interface.

The S-Class will have both its standard length and stretched Maybach and Maybach Pullman body styles. The short-wheelbase option sold overseas could be dropped, though. We also expect the current S-Class Coupe and Cabriolet to be phased out. A roomier next-generation SL-Class with 2+2 seating is expected to fill the void.