The sixth-generation Mercedes-Benz C-Class is the first combustion-engined model from the German manufacturer to go electrified-only.
It also brings technology from the S-Class flagship alongside a design overhaul in an effort to take on the latest BMW 3 Series.
The saloon and estate have been revealed simultaneously ahead of a 30 March on-sale date, followed by first deliveries this summer. Starting prices are likely to be bumped up slightly to around £35,000 and £38,000 respectively.
The new W206 C-Class has been brought into line with its newer A-Class, CLA, CLS and E-Class range-mates, primarily by way of shorter overhangs, a more angular front end and new light-cluster designs.
The external proportions of Mercedes' best-selling model remain familiar, but it has received design tweaks all round with the aim of appearing "in motion at a standstill". The bonnet features a pair of prominent 'power bulges' and the glasshouse has been moved slightly farther back to give the impression of a cab-rearwards design.
Creases and character lines have been kept to a minimum, Mercedes said, in an effort to accentuate the shoulder line, while the estate gains a more obviously inclined roofline for a "sporty touch without functional compromises".
As with all Mercedes models, the front-grille design differs according to the trim level, with higher-specification cars gaining added chrome and decorative features.
The wheelbase on both models has been increased by 25mm to 2865mm and the overall length is up by 65mm. This latter increase is said to give extra passenger room in the cabin, while the estate's boot gains an additional 30 litres of cargo capacity.
As first reported by Autocar, the new C-Class is powered exclusively by electrified four-cylinder engines, right up to the (as-yet-unseen) AMG C63 hot range-topper, with plug-in and mild-hybrid technology rolled out across the range for better efficiency and thus reduced emissions.
The W206 remains available with a choice of diesel and petrol engines, although each is now equipped as standard with a 48V belt-integrated starter generator (BISG). This recovers energy under deceleration to provide a power boost of up to 20bhp, allow for 'gliding' at a cruise and render the start-stop process "almost imperceptible".
The petrol line-up opens with the 1.5-litre C180, which produces 168bhp and 194lb ft, can crack the 0-62mph sprint in 8.6sec and tops out at 144mph. The C200 shares the C180's 1.5-litre capacity but makes 201bhp and 221lb ft for a 0-62mph time up to 1.5sec quicker than the entry-level model and a top speed of up to 153mph. And the 2.0-litre C300 produces 255bhp and 295lb ft and hits 62mph from rest in as little as 6.0sec.
The Mercedes-AMG Formula 1 team worked with the C-Class development team to introduce a new turbocharger with better responsiveness and efficiency. Combined with the electrical assistance, this helps the petrol car achieve a WLTP average of between 36-46mpg, depending on specification, while emitting 141-180g/km of CO2.
There are three diesel options, each using an updated version of Mercedes' 2.0-litre unit, which has been boosted in capacity by 42cc. The entry-level C200d makes 161bhp, the mid-level C220d produces 197bhp and the top-rung C300d has 261bhp while also being the quickest variant from rest to 62mph, at 5.7sec. The diesel car is capable of a 57.6mpg average, and emits 131-152g/km.
The C200, C300 and C220d are each available with Mercedes' 4Matic four-wheel drive system. This can send more torque to the front axle than before for improved dynamics, weighs less and is more frugal, thanks to reduced friction in the transfer case.
A nine-speed automatic gearbox is now standard fitment on all models, in line with Mercedes' plan to gradually phase out manual gearboxes, and is said to be lighter and more efficient than the previous unit.
The "significantly more electric" plug-in hybrid C300e will be reintroduced to the range shortly after launch, upping the WLTP-certified electric-only range from 34 miles to 62 miles courtesy of a new 25.4kWh battery pack, up from 13.5kWh, which is mounted under the boot floor.
Using a 126bhp permanently excited synchronous electric motor and a 198bhp petrol engine, the C300e packs a combined 304bhp and 406lb ft, making it "not only very efficient but also decidedly sporty".
It can operate on electricity alone at speeds of up to 87mph and can be charged in as little as 30 minutes with a 55kW fast charger (although an 11kW device is fitted as standard). It also benefits from an adjustable energy recuperation system that can top up the battery at up to 100kW when coasting or decelerating.
This PHEV also gains a hybrid-specific route-planning function that uses the sat-nav, topography and traffic data to map out the most efficient route, enabling, for example, automatic prioritisation of the electric motor in urban areas.
The influence of the latest S-Class on the new C-Class is evident, chiefly in the shift from a horizontal, 'free-floating' infotainment display to a portrait-orientated, tablet-style central touchscreen between the front seats.
This measures 10.25in as standard, while an 11.9in item, which is fitted as standard in the S-Class, is optionally available. The screen is angled slightly towards the driver for ease of use and visibility on the move. A high-definition LCD digital instrument display, which appears to float above the dashboard, can be specified in 10.25in or 12.3in forms.
The two screens offer three display styles with different colours and motifs: Discreet shows only "what is essential", Classic is said to use a "familiar" display layout and Sporty switches to a red theme, swapping the usual rev counter for a more "dynamic" display.
There's a choice of Navigation, Assistance or Service operating modes, while optional ambient lighting with optical fibre technology can be specified.
The C-Class is the second model in Mercedes' line-up to use the second-generation MBUX infotainment system, which brings an upgraded version of the firm's Hey Mercedes voice assistant, various smart home functions, an integrated music streaming platform, over-the-air updates and optional 'augmented video' software, which digitally renders the car's surroundings on the central touchscreen to "make navigation much easier, especially in urban areas". The system is unlocked using a fingerprint scanner below the screen and can be bolstered with the optional addition of a colour head-up display.
Elsewhere, jet engines have inspired a subtle redesign for Mercedes' distinctive air vents, and the gear shifter and rotary dial have been removed; most infotainment functions are now operated via touch-sensitive pads on the steering wheel.
The padded central armrest has been lightly reshaped but retains its split-fold opening lid, while subtle tweaks to the door panels include the relocation of the window and lock buttons to the grab handle and the addition of a new 'floating' panel for the seat controls and door handle.
Revised front four-link and rear multi-link suspension is said to provide " the basis for a high level of suspension, ride and noise comfort, agile handling and driving fun". Air suspension is standard on the rear axle of all plug-in hybrid models, with sports suspension and continuously adjustable damping optional across the range.
More significantly, the C-Class follows the luxury-focused S-Class in gaining optional rear-axle steering for improved agility and a reduced turning circle. The rear wheels steer up to 2.5deg in the same direction as the fronts at speeds above 37mph, which improves high-speed stability, and allows for reduced steering input in tight bends.
Upgrades to the Driving Assistance Package include a more advanced Active Distance Assist function, 360deg multilane recognition for the Active Steering Assist programme and enhanced automatic traffic-sign recognition.
New headlights are LED units as standard across the range, while the S-Class's innovative Digital Light system is an option, bringing 1.3 million pixels resolution per headlight and the ability to project warning symbols and guide lines on to the road. In another S-Class-inspired touch, the rear seats are now optionally heated and available with a deep-tissue massage function.