In the 21 years that Nissan has been selling cars in America labeled as Infinitis, the brand has been struggling to cement an identity for itself. With its award-winning G-series, it established that it could build luxury cars that can battle against the best luxury sport cars on the market. But when it dropped its top-of-the-line Q series from the lineup, many wondered what would come of the brand. We're still not sure, but we think the new M-series—specifically, the new M56—is helping clear that all up. Bumped to the top, the M56 is now Infiniti's halo car: its showcase for all the new technologies Infiniti has been working on (and hopes to send downstream to its other offerings). We took the M56 S out for a test spin to see if Infiniti's future is secure; read on to find out.