The Q Inspiration Concept is due to have its proper debut at the Detroit motor show, which kicks off on January 14.
Infiniti isn't revealing many specifics about the vehicle before that, beside saying the car's styling is designed to stand out in the "era of advanced powertrains".
According to Karim Habib, Infiniti head of design, the concept experiments with "new proportions in an established segment" thanks to the "arrival of smarter, compact powertrains".
Habib says the Q Inspiration's "shorter hood and elongated body" brings improved "interior wellbeing, comfort and space".
Designed to show off Infiniti's new design language, the look of the Q Inspiration Concept is widely anticipated to translate into a new range-topping sedan.
At present, Infiniti has only two sedans in its model range. The Q50 was unveiled back in 2013, and does battle with the BMW 3 Series, Mercedes-Benz C-Class, Audi A4 and Lexus IS. The larger Q70 dates back to 2009, when it was still known as the Infiniti M.