Ford Mustang is celebrating its 50th anniversary with something old and something new.

"From day one, we knew if we were going to build a new Mustang, we had to do it right," Dave Pericak, Ford Mustang chief engineer, said.

Today, Ford revealed its 2015 Mustang with the help of Gail Wise, the first person to ever own a Mustang, Associated Press reports. Wise purchased the car in the spring of 1964 from a Ford dealership in Chicago for $3,347. Once she brought the convertible on the road, she was met with honks from drivers waving her down.

"I felt like a movie star," Wise said.

Wise brought her original Mustang to today's unveiling. The car still sits in her garage in Chicago.

"It was sporty. It was perfect. It went zoom zoom," she said.

Over 9 million sales later, a new commercial spot for the 2015 Mustang features a more contemporary spokesperson, Sienna Miller. The spot was shown in Ford's Barcelona, Dearborn, Mich., Los Angeles, New York and Sydney unveilings.

"I do love an American accent," Miller says in her only line in the commercial.

The car features a 3.7-liter V6 with an estimate 300 horsepower. A 2.3-liter turbocharged four-cylinder will be offered as well, which will produce more than 305 horsepower and 300 lb. - ft of torque.

"Mustang is definitely more than just a car - it is the heart and soul of Ford," Raj Nair, the Ford group vice president of global product development, said.

Meanwhile, the GT will be powered by a V8 engine, 420 horsepower and 390 lm. -ft. of torque. The car will require premium fuel.

Mustang's actual 50th anniversary is on April 17, 2014. The next-gen pony car will be available in the fall.

According to Jim Farley, executive president of Ford global marketing, sales and service and Lincoln, the goal of the Ford Mustang remains the same after 50 years: "a contemporary interpretation of Mustang - an American automotive icon that symbolizes optimism and freedom for millions of people around the world."

Check out Ford 2015 Mustang spot featuring Sienna Miller below: