In January 2011, US Rep. Gabrielle Giffords was shot in the head while meeting with constituents near Tucson, Arizona.

Six people were killed in the mass shooting that day, but Giffords survived and eventually returned to the House.

She resigned in 2012 to focus on her health and recuperation. Since then, she has become a key voice on gun violence prevention.

A new CNN film, "Gabby Giffords Won't Back Down," tells the story of her relentless fight to recover following the 2011 assassination attempt. The film, which airs Sunday at 9 p.m. ET, also documents her new life as an activist.

Newly elected US representatives — including Giffords, second from top right — prepare for a freshman class picture on the House steps in 2006. Giffords, a Democrat, represented Arizona's 8th District from 2007 until her resignation in 2012.
Newly elected US representatives — including Giffords, second from top right — prepare for a freshman class picture on the House steps in 2006. Giffords, a Democrat, represented Arizona's 8th District from 2007 until her resignation in 2012.
Tom Williams/Roll Call/Getty Images
Giffords gives a tour of the US Capitol's Statuary Hall in 2008. Joining her are Japanese astronaut Akihiko Hoshide, left, and her husband, NASA astronaut Mark Kelly. Kelly has since become a US senator.
Giffords gives a tour of the US Capitol's Statuary Hall in 2008. Joining her are Japanese astronaut Akihiko Hoshide, left, and her husband, NASA astronaut Mark Kelly. Kelly has since become a US senator.
Bill Clark/Roll Call/Getty Images
Giffords addresses supporters in Tucson, Arizona, after winning reelection in 2010.
Giffords addresses supporters in Tucson, Arizona, after winning reelection in 2010.
Tom Willett/Getty Images
A framed photograph of Giffords is seen among candles as a vigil is held outside a hospital in Tucson on January 8, 2011. Giffords was shot that day as she was meeting with constituents in front of a grocery store. Six people were killed. The gunman, Jared Lee Loughner, was sentenced to life in prison without parole in 2012.
A framed photograph of Giffords is seen among candles as a vigil is held outside a hospital in Tucson on January 8, 2011. Giffords was shot that day as she was meeting with constituents in front of a grocery store. Six people were killed. The gunman, Jared Lee Loughner, was sentenced to life in prison without parole in 2012.
Tom Willett/Getty Images
Giffords' husband, Mark Kelly, holds his wife's hand in her hospital room on January 9, 2011.
Giffords' husband, Mark Kelly, holds his wife's hand in her hospital room on January 9, 2011.
US Rep. Gabrielle Giffords' office/Getty Images
Giffords is pictured the day before she underwent skull surgery in Houston in May 2011. It was one of the first photographs of her released after the shooting.
Giffords is pictured the day before she underwent skull surgery in Houston in May 2011. It was one of the first photographs of her released after the shooting.
P.K. Weis/Giffords Campaign/Getty Images
Kelly hugs his wife after he received the Legion of Merit from Vice President Joe Biden, left, during his retirement ceremony in Washington, DC, in October 2011.
Kelly hugs his wife after he received the Legion of Merit from Vice President Joe Biden, left, during his retirement ceremony in Washington, DC, in October 2011.
Pete Souza/The White House/Getty Images
Giffords leads the Pledge of Allegiance during a vigil held on the one-year anniversary of the shooting.
Giffords leads the Pledge of Allegiance during a vigil held on the one-year anniversary of the shooting.
Jonathan Gibby/Getty Images
President Barack Obama embraces Giffords before his State of the Union address in January 2012.
President Barack Obama embraces Giffords before his State of the Union address in January 2012.
Saul Loeb/Pool/Getty Images
Giffords resigned from Congress in January 2012 to focus on her recovery.
Giffords resigned from Congress in January 2012 to focus on her recovery.
Mark Wilson/Getty Images
Giffords, Kelly and then-Vice President Joe Biden watch Obama sign the Ultralight Aircraft Smuggling Prevention Act in February 2012. The bill was the last piece of legislation Giffords voted on before she resigned.
Giffords, Kelly and then-Vice President Joe Biden watch Obama sign the Ultralight Aircraft Smuggling Prevention Act in February 2012. The bill was the last piece of legislation Giffords voted on before she resigned.
Mark Wilson/Getty Images
Giffords and Kelly speak at the Simon Wiesenthal Center's annual tribute dinner, where they received Medals of Valor in May 2012.
Giffords and Kelly speak at the Simon Wiesenthal Center's annual tribute dinner, where they received Medals of Valor in May 2012.
Valerie Macon/Getty Images
US Rep. Debbie Wasserman Schultz, head of the Democratic National Committee, joins Giffords on stage at the Democratic National Convention in September 2012.
US Rep. Debbie Wasserman Schultz, head of the Democratic National Committee, joins Giffords on stage at the Democratic National Convention in September 2012.
Brendan Smialowski/AFP/Getty Images
Giffords and Kelly arrive for a Senate Judiciary Committee hearing about gun control in January 2013. The former congresswoman delivered an opening statement to the committee, which was meeting for the first time since the mass shooting at Sandy Hook Elementary School in Newtown, Connecticut.
Giffords and Kelly arrive for a Senate Judiciary Committee hearing about gun control in January 2013. The former congresswoman delivered an opening statement to the committee, which was meeting for the first time since the mass shooting at Sandy Hook Elementary School in Newtown, Connecticut.
Chip Somodevilla/Getty Images
Giffords and Kelly attend a March 2013 news conference in Tucson that urged Congress to provide stricter gun control in the United States. At left, Roxanna Green holds a photo of her daughter, Christina Taylor Green, who was killed in the 2011 shooting.
Giffords and Kelly attend a March 2013 news conference in Tucson that urged Congress to provide stricter gun control in the United States. At left, Roxanna Green holds a photo of her daughter, Christina Taylor Green, who was killed in the 2011 shooting.
Joshua Lott/Getty Images
Giffords attends a dedication ceremony in April 2013 at the US Capitol Visitor Center in Washington D.C. A meeting room was named for Gabriel Zimmerman, a member of Giffords' staff who was murdered in the 2011 shooting.
Giffords attends a dedication ceremony in April 2013 at the US Capitol Visitor Center in Washington D.C. A meeting room was named for Gabriel Zimmerman, a member of Giffords' staff who was murdered in the 2011 shooting.
Chip Somodevilla/Getty Images
Jill Biden, wife of Biden, smashes a champagne bottle on the bow of a US Navy vessel that was being named in Giffords' honor in June 2015. Giffords and Kelly are on the right.
Jill Biden, wife of Biden, smashes a champagne bottle on the bow of a US Navy vessel that was being named in Giffords' honor in June 2015. Giffords and Kelly are on the right.
Mike Brantley/AL.com/AP
Giffords rides in a charity bike race in Tucson in November 2015.
Giffords rides in a charity bike race in Tucson in November 2015.
Mamta Popat/Arizona Daily Star/AP
Giffords joins Democratic presidential candidate Hillary Clinton at a Women for Hillary event in New York City, one day before the New York primary in 2016.
Giffords joins Democratic presidential candidate Hillary Clinton at a Women for Hillary event in New York City, one day before the New York primary in 2016.
Kathy Willens/AP
Giffords attends New York University's commencement ceremonies in 2017.
Giffords attends New York University's commencement ceremonies in 2017.
Dia Dipasupil/Getty Images
Giffords watches US Rep. Mike Thompson sign a 2019 bill that would expand background checks for sales of firearms. It did not make it through the Senate.
Giffords watches US Rep. Mike Thompson sign a 2019 bill that would expand background checks for sales of firearms. It did not make it through the Senate.
Al Drago/Bloomberg/Getty Images
Giffords and Kelly attend the Tucson premiere of the film "Gabby Giffords Won't Back Down" in July 2022.
Giffords and Kelly attend the Tucson premiere of the film "Gabby Giffords Won't Back Down" in July 2022.
Chris Coduto/Getty Images
President Biden awards Giffords with the Presidential Medal of Freedom in July 2022.
President Biden awards Giffords with the Presidential Medal of Freedom in July 2022.
Kevin Lamarque/Reuters
Giffords is joined by Florida gubernatorial candidate Charlie Crist, left, as they arrive at a restaurant in Miami in September 2022. State Democratic officials joined Giffords as she continued a bus tour against gun violence.
Giffords is joined by Florida gubernatorial candidate Charlie Crist, left, as they arrive at a restaurant in Miami in September 2022. State Democratic officials joined Giffords as she continued a bus tour against gun violence.
Rebecca Blackwell/AP