Even with much of the dashboard hidden from view, we can see the new Z4 has a free-standing high resolution infotainment screen and an iDrive controller in the centre tunnel.
A description sheet stuck to the dashboard camouflage reveals the new Z4 is codenamed G29. The prototype seen here is a s20i model with a 145kW/320Nm B48 2.0-litre turbocharged four-cylinder engine powering the rear wheels via a six-speed manual transmission.
Interestingly, the sheet also has a section stating "SoP: 11/18". For most manufacturers, this is known to indicate a month and year, suggesting the new Z4 will launch (or enter production) in November next year.
MORE: 2019 BMW Z4 first-drive review
Under the skin, the new Z4 will use a new rear-wheel drive sports car platform co-developed with Toyota. Reports indicate all-wheel drive may offered as an option.
BMW will reportedly offer the new Z4 with a choice of turbocharged four- and six-cylinder petrol engines. Toyota's version, said to revive the Supra name, will be offered as a coupe and may feature a hybrid drivetrain.
These first spy photos of the new Z4 in over half a year show a car that's wearing similar levels of disguise to earlier prototypes, as well as false body panels in a number of strategic positions.
While we may not be able to discern all of the roadster's styling details, we can clearly see the new car will stick to the Z3 and Z4 formula including a long bonnet, a small two-seat cabin just ahead of the rear axle, and a short rear deck.
Unlike the first two generations of the Z4, the new car will not feature a folding hardtop. Instead, the Z4 will be equipped with an electrically operated soft-top, although rumours suggest a solid hardtop will be offered down the line.
While many in the industry assumed the new car will be branded as the Z5, Ludwig Willisch, head of BMW North America, revealed earlier this month the new car will 'probably' be known as the Z4.