The Conspirator is a 2010 American mystery historical drama film directed by Robert Redford and based on an original screenplay by James D. Solomon.

The film tells the story of Mary Surratt, the only female conspirator charged in the Abraham Lincoln assassination and the first woman to be executed by the US federal government.

It stars Robin Wright as Mary Surratt, together with James McAvoy, Justin Long, Evan Rachel Wood, Jonathan Groff, Tom Wilkinson, Alexis Bledel, Kevin Kline, John Cullum, Toby Kebbell, and James Badge Dale.

[6][7] On April 14, 1865, five days after the Civil War ends with Robert E. Lee's surrender to Ulysses S. Grant at Appomattox Court House, Virginia, lawyer and Union veteran Frederick Aiken, with his friends, William Thomas Hamilton and Nicholas Baker, and his wife, Sarah Weston, celebrate.

German immigrant and carriage repair business owner George Atzerodt is assigned to kill Vice President Andrew Johnson, but becomes afraid, gets drunk, and runs away.

Booth stabs diplomat and military officer Henry Rathbone, who was a guest in Lincoln's box, and leaps onto the stage, shouting, "Sic Semper Tyrannis!

A crowd, including Aiken, Hamilton, and Baker, watches in horror as the unconscious President is taken to a nearby boarding house, where he dies early the next morning.

Booth and David Herold manage to evade capture for some days, but Union soldiers find a barn where they suspect the conspirators are hiding and set it on fire.

Reverdy feels unable to defend Surratt because he is a Southerner and asks a reluctant Aiken who is a Northerner to take over the defense.

He describes John's meetings with Booth, and points out Herold, Powell, and Atzerodt as frequent guests in Mary's boarding house.

Aiken arrives at the Century Club to attend a party and discovers that his membership has been revoked for defending Mary Surratt.

The epilogue goes on to state that a year later, the US Supreme Court ruled that citizens were entitled to trial by a civilian jury, not a military tribunal, even in times of war (Ex parte Milligan), and that a jury of Northerners and Southerners could not agree on a verdict for John Surratt, and he was freed.

Fort Pulaski National Monument, located east of Savannah, served as the military prison in the film.

The Mary E. Surratt Boarding House still stands, and is located at 604 H Street NW in Washington D.C.'s Chinatown.

The website's critical consensus states that "The Conspirator is well cast and tells a worthy story, but many viewers will lack the patience for Redford's deliberate, stagebound approach.