The images shown here appeared briefly on the carmaker's Canadian website, although they have since been removed. Official details of course are still to be revealed.
The Q50 is also the first new model to carry Infiniti's restyled Q branding, with Q60 Coupe and Convertible models set to replace the current G two-door models in the near future.
- MORE: Click here for all the details on the new naming system.
The Q50 evolves Infiniti's hooked lighting design, while the back-end shows long tail-lights stretching into the rear quarter panels.
The theme continues again the cabin, the Q50 evolving the look of the brand's current dash design. A new centre display arrangement is also featured, including two large screens.
Details for the new model have not been released, but it is known the Q50 is larger than its predecessor, with power in the flagship model expected to come from an updated version of the existing V6 engine.
A four-cylinder engine, sourced from development partner Mercedes-Benz, is also expected to be offered in some markets - likely replacing the 2.5 V6 in the current G25.
It's unclear how Infiniti will set variants in the Q50 range apart, with the numbers in the new names "representing hierarchy within the range", rather than engine capacity.
One possibility is that an entry Q50 variant would wear a Q51 badge, with higher-spec and more powerful models taking Q52, Q53 - and so on.
For now, we must wait until the new sedan's unveiling in Detroit this week.
Note: leaked images via myG37 forums.