Last year in September, we got our first look at the breathtaking Mercedes-Benz Vision EQS concept car. Call it a Porsche Taycan rival or the all-electric version of the Mercedes-Benz S-Class, but its two-tone bodywork immediately won us over. Now, the EQS is even closer to becoming a reality after Mercedes teased us with pictures of the concept alongside an actual production prototype in Southern California.

Unfortunately, like the spy shots captured previously, heavy camouflaging made it just about impossible to decipher which of the concept's many intriguing design details have made it onto the prototype. What we can see is that both share a steeply angled windshield and a rounded front end, along with a body style that looks a lot more like a five-door hatchback.

Mercedes describes the Vision EQS as the "first milestone on the way to CO2-neutral mobility of the future". The "one bow" design concept wears 24-inch multi-spoke wheels, although the prototype appears to be wearing more manageably-sized items that don't fill out every available inch of the arches.

The Vision EQS' rear lights are integrated into the body and feature 229 individual LED stars - it's not clear how closely the prototype follows this design, although, like the concept, the prototype features a coupe-style roofline and frameless doors. Not to be completely outdone, the curvaceous front end contains 188 of its own individual LEDs.

The available images of the prototype were restricted to the exterior, but previous spy shots do indicate that it will share a layout with the next S-Class. What is also likely is that at least some - if not all - of the concept's sustainable materials like Dinamica microfiber and artificial leather will be carried over. The Vision EQS is propelled by two electric motors (one at each axle), and a battery which has been integrated into the floor. The combined power output is 469 horsepower and 560 lb-ft of torque.

With a 0-60 mph sprint time of 4.5 seconds, it's not quite as quick as the Porsche Taycan, but then again, this is still more of a new-age Mercedes-Benz luxury sedan than a sports car, so performance remains plentiful.

Although we still don't know exactly when to expect a market launch of the EQS, Mercedes' latest teaser is at least confirmation that development is forging ahead rapidly. Then again, there's the knowledge that the brand's first all-electric SUV - the EQC - has had its launch pushed back to 2021 due to being unable to meet early customer demands. Hopefully, the same production issues don't afflict the EQS and we'll get to see it sooner rather than later.