Sandra Bullock Turns 50: Her Evolution From Speed to Gravity

Bullock played Diane, a lovesick scientist, in 1992's "Love Potion Number 9," one of her first major credits. Before "Love Potion," Bullock had been in a few TV movies and played the lead in the short-lived NBC series "Working Girl."

Bullock's real breakthrough came in 1994, starring alongside Keanu Reeves in "Speed" as the courageous bus passenger Annie Porter. The film won two Academy Awards and resulted in a sequel, in which Bullock reprised her role.

In 1995, Bullock (shown here with Monica Keena) starred in "While You Were Sleeping" as Lucy Moderatz, the Chicago transit worker who falls in love with a guy in a coma...and then his brother. The film was a huge commercial success, grossing $182 million worldwide with only a $17 million budget, and garnered the first of five Golden Globe nominations for Bullock.

Sandra Bullock plays an undercover FBI agent attempting to walk the walk as a beauty contestant in 2000's "Miss Congeniality." The romantic comedy featured Michael Caine (left) and garnered a second Golden Globe nomination for Bullock.

Bullock and Nicole Kidman played witch sisters trying to be their family's love curse in 1998's "Practical Magic." The film opened at number 1 the weekend of its release but was not well-received by critics.

Bullock appeared alongside acting greats Ellen Burstyn, Maggie Smith, Fionnula Flanagan and Shirley Knight (pictured) in 2002 with "Divine Secrets of the Ya-Ya Sisterhood." Bullock took the role of playwright Siddalee Walker, the daughter of Ellen Burstyn's Viviane Walker, who was played by Ashley Judd in flashbacks.

The 2005 film 'Crash' won six Oscars and the Screen Actors' Guild award for best cast—which included Bullock, Larenz Tate, Brenden Fraser, and Chris 'Ludacris' Bridges (pictured). For the best picture win, 'Crash' beat out possibly the most critically acclaimed film of the year, 'Brokeback Mountain.'

Bullock co-starred with Ryan Reynolds in the 2009 romantic comedy "The Proposal." The movie featured Bullock's character Margaret trying to use her assistant (Reynolds) as fake significant other to obtain an immigration visa. "The Proposal" was widely successful, grossing over $300 million worldwide on a $40 million budget.

Bullock picked up her "Best Actress" Oscar playing Leigh Anne Tuohy alongside Jae Head and Quinton Aaron (pictured here) in 2009's "The Blind Side." The film, inspired by the real-life story of NFL player Michael Oher, was also nominated for "Best Picture" in a year where 10 films were nominated for the category.

Bullock and Melissa McCarthy (right) played two polar-opposite law enforcement officers in 2013's "The Heat." It became 2013's second-highest grossing comedy (after "We're the Millers"). Rumors of a sequel began to swirl even before the film's release.

Sandra Bullock in 'Gravity.'