BMW is preparing to replace the 3-Series Coupe with a new 4-Series, and it brought a thinly veiled version of the new two-door to the 2013 Detroit Auto Show in the form of a 4-Series Coupe Concept.

This concept features both the latest interpretation of BMW's design language, but also the latest implementation of BMW's new naming strategy.

The concept's design builds off of the latest 3-Series with an aggressive front end, elegant greenhouse, sleek curves, and a taut well defined rear end. We actually liked the unique accent on the front fender panel once we saw it in real life. The headlights are all-LED and have a more swept-back look, reflecting a new take on BMW's "angel eyes" design.

The design story doesn't stop with the exterior. The interior features some truly fantastic design and leather execution. We can only hope this is the way forward for BMW, and not merely a concept car interior.

You can expect the 4-Series Coupe engine lineup to be the same as the 3-Series when it goes on sale. That means there will likely be a 428i model with a 2.0-liter turbo four-cylinder engine, and a 435i model featuring a 3.0-liter twin-turbo six-cylinder engine.

Stay tuned as more we get closer to the production reveal of the 4-Series later this year. Until then, you can check out all the details regarding the 4-Series Coupe Concept here, and follow all our coverage of the 2013 Detroit Auto Show here.