Four cylinders, compact proportions, supercar pace — the CLA 45 S is AMG's sharpest road weapon in a suit.

Under the hood lives the M139 — a 2.0-litre turbocharged four-cylinder producing 421 PS and 500 Nm, recognised at its launch as the world's most powerful series-production turbocharged 2.0-litre four-cylinder engine. Bury the throttle and it answers with a ragged, high-revving scream and signature AMG crackle on every upshift.

The AMG Performance 4MATIC+ all-wheel-drive system vector-controls grip corner to corner, while the AMG SPEEDSHIFT DCT 8-speed dual-clutch fires off ratios fast enough to carry you from standstill to 100 km/h in 3.9 seconds — in a car that looks like a stylish liftback from the outside.

Widened arches, a Panamericana grille and aggressive aerodynamics announce intent long before you press the throttle. Arrive faster than anyone expects.