Compared to the last prototype, spied on the Nurburgring in May 2017, this latest car wears significantly less camouflage.
Gone are most of the coverings around the head- and tail-lights, the disguise around the grille and lower air intakes, and the false body panels along the car's flanks.
Despite the prototype's swirly outer layer, we can see a vehicle that's not too dissimilar from the Concept Z4 launched at last year's Pebble Beach Concours d'Elegance.
In addition to the working door handles, and larger lighting units, the production car seems to feature bumpers that aren't as aggressively scalloped.
The new Z4 does retain the concept's integrated boot lip spoiler, and studded chrome inlay for its double-kidney grille, although the bonnet panel no longer reaches the top edge of the grille.
As we've seen in earlier spy photo sets, the new Z4 will ditch the current car's folding hardtop mechanism in favour of a soft-top.
MORE: 2019 BMW Z4 first-drive review
With sports car sales shrinking across the globe, the new Z4 is being developed alongside the replacement for the long-departed Toyota Supra.
Both will share a platform, and many of their mechanical and electrical components. Indications are the Z4 will be exclusively marketed as a convertible, while the Supra will be a coupe.
Externally, the only things that point to their common heritage are their similar dimensions, shared wing mirrors, and their long bonnet, cab-backwards design.