If the Infiniti M56 were a figure in ancient Greek legend, it might be an Amazon - one of the strong, muscular and beautiful female warriors who fought with the Trojans. This motoring machine is both curvy and sleek, and it has sculpted shoulders. Fashioned with a whittled waist and commanding hindquarters, it is powered by a fierce V-8 engine and silky-smooth, seven-speed automatic transmission.

The 2012 Infiniti M56 carries forward the M nameplate used since 1990 on various mid-luxury models by Infiniti, Nissan's luxury division. The 4-door, 5-passenger M56 is likely priced shopped against the BMW 550i, the Lexus GS 460 and Mercedes-E550 Sedan among other luxury sport sedans in this segment.

The Infiniti M lineup was reintroduced last year after a hiatus with cars in this class. The 2012 Infiniti M56 isn't a brand-new iteration, but an update to last year's all-new model and a hail to the popular, sporty M line-up. There are a few minor changes to options packages as well as the significant addition of a hybrid drivetrain to the Infiniti stable.

 The 2012 Infiniti M Hybrid uses Nissan's first hybrid technology that was developed by this Japanese automaker's in-house team and Nissan claims nearly doubles the fuel economy. Along with the Nissan Leaf, it showcases the all-new Vehicle Sound for Pedestrians with an alert for pedestrians and the blind, when the hybrid is operating in all-electric mode.

The 2012 Infiniti M56 is one of three models in the M line-up with the other two model being the M35 Hybrid and the base M37. The M56 is motivated by a V-8 that makes 420 horsepower and 417 pound-feet of torque, and it is mated to a fuel-saving, seven-speed automatic transmission with a manual shift mode. Rear-drive is standard and all-wheel drive is available (this version is designated by a 56x badge). The hybrid model has a V-6 that delivers 320 horsepower and is rated at 32 mpg.

The large, cushy cockpit of the 2012 Infiniti M56 is made exceptionally comfortable and convenient through features like 10-way power adjustments for the driver and front passenger seats that can be heated and cooled, and Intelligent Keys, which are sort of like individual thumb-drives that store information about seat positions, climate control settings, audio preferences and navigation information for each driver. A heated steering wheel, Bluetooth and a rearview monitor also are standard.

Although the 2012 Infiniti M56 looks gorgeous, its sweeping waves of sheet metal add up to more than a pretty face. The M56 has a low coefficient of drag (0.27), and it makes good elbow room for five passengers along with the ability to store their gear in a large trunk which has a pass-through to the rear seat for long items such as skis. The headlamps have a crystal-like sparkle, and the trunk shape has been crafted to work like a spoiler. A power moonroof and automatic on/off headlights are standard, as are 18-inch aluminum alloy wheels (20-inch wheels come with the Sport option package).