Le Miroir à Deux Faces, or The Mirror Has Two Faces, is the title of an enjoyable 1958 French comedy about a frumpy, unhappy woman who finds herself the center of attention after she undergoes beautification via major plastic surgery. Its plot could just as well have been the life story of Infiniti's original M45 sedan. Though well built and certainly fast, the cruiser simply didn't have the style, features or interior room to turn the heads of luxury car buyers. Infiniti put the car on the operating table for an intensive overhaul, and in 2006, the M was reborn as two stunning, capable, all-new performance sedans -- the M35 and M45.

With its understated good looks, the 2007 Infiniti M35 is attractive, but its appeal isn't merely cosmetic. The car's cabin is decadently spacious, with class-leading amounts of head- and legroom. Still, its accommodations don't quite equal those of competitors like the Audi A6 and Lexus GS 300 in terms of design and materials quality. Most folks, however, should find the M35's interior warm and inviting, bolstered by an extravagant array of standard amenities.

But what makes the Infiniti M35 a true knockout is the power resting beneath its hood. The car is motivated by a brawny 3.5-liter V6 that offers 275 horsepower. It's paired with a five-speed automatic transmission that offers an impeccable degree of responsiveness, making for fun times behind the wheel. Topping things off is a double-wishbone front, multilink rear suspension that doles out just the right mix of compliance and firmness.

If you like your luxury performance sedans heavy on luxury, the 2007 Infiniti M35 isn't your best option. Though pleasant, its cabin simply can't match rivals like the Audi A6 when it comes to chrome-ringed, leather-trimmed glamour. However, if performance and handling are your primary concern, you'll be happy with this Infiniti, which outdistances the competition when the rubber hits the road.

The 2007 Infiniti M35 is a midsize luxury sport sedan. Buyers have the choice of three trims: base, x AWD and Sport. The base trim's generous standard features list includes leather upholstery, a 10-way power-adjustable driver seat, one-touch up-and-down power windows, dual-zone automatic climate control, wood trim, an auto-dimming rearview mirror, heated outside mirrors and an in-dash six-CD changer with MP3 playback capability. The x AWD trim adds all-wheel drive and heated and cooled front seats. The Sport trim trades wood accents for aluminum ones and adds rear active steering, sport-tuned suspension, upgraded wheels, adaptive xenon HID headlamps and front sport seats with larger bolstering.

Various option packages offer features such as a navigation system, a center-console-mounted DVD player, rearview camera, adaptive cruise control (which automatically adjusts your speed to maintain a selected following distance), a lane departure warning system, reclining/heated rear seats and a 14-speaker Bose surround-sound audio system.

The M35 features a 3.5-liter V6 that pumps out 275 hp and 268 pound-feet of torque. A five-speed automatic with automanual capability and downshift rev-matching is standard. The car is offered in both rear- and all-wheel-drive versions. An M35x AWD we tested sprinted to 60 mph in 6.9 seconds and ran the quarter-mile in 14.9 seconds. The V8-powered M45 hit 60 in 5.7 seconds and completed the quarter in 14.4 seconds.

Standard on the M35 are antilock disc brakes (with brake assist), stability control, front-seat side airbags, full-length side curtain airbags and active head restraints for the front seats. An available lane departure warning system alerts the driver of unintended lane drifting. In IIHS crash tests, the M35 luxury sport sedan scored a "Good" rating -- the highest possible -- for both frontal and side impact protection.

Though not as athletic as the V8-equipped M45, the M35's V6 still provides plenty of punch for most drivers. Braking performance is impressive, and a firmly tuned suspension provides excellent balance in the corners. The trade-off is steering that can feel a bit raw around town and a suspension that sharpens road irregularities, especially in the firm Sport model. When experienced on the highway, the car also exhibits a fair degree of engine and road noise. These flaws certainly don't make the 2007 Infiniti M35 uncomfortable to ride in, but it is noticeably less serene than others in its class.

The 2007 Infiniti M35's interior is well appointed and features leather seating and Brazilian Rosewood trim (aluminum with the Sport model). Its firm seats are highly adjustable, comfortable and heavily bolstered. Overall, the M's interior is well-built and attractive. However, the bar is raised pretty high in this category (which is, after all, home to cars like the Audi A6), and the M35's interior isn't quite as elegant and thoughtfully designed as that of others in its class. Relative to its rivals, materials quality is a bit spotty, and the layout of the center stack controls isn't as clean and intuitive as we'd like.