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Convicted killer Alex Murdaugh admitted Thursday in federal court to stealing millions of dollars from his former clients, the first time he has ever pleaded guilty to a crime.

Murdaugh, 55, was sentenced in March to life in prison for fatally shooting his 52-year-old wife, Maggie Murdaugh, and their youngest son, Paul Murdaugh, 22, in June 2021. He has insisted he's innocent and is appealing the jury verdict.

The disbarred attorney pleaded guilty to 22 counts in South Carolina U.S. District Court, including bank fraud and money laundering, for the theft of more than $9 million, as part of a plea agreement.

"I want to take responsibility. I want my son to see me take responsibility. It’s my hope that by taking responsibility that the people I’ve hurt can begin to heal," said Murdaugh, standing in his yellow prison jumpsuit.

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Murdaugh, who famously had a raging opioid addiction, told U.S. District Judge Richard Gergel that he has been sober for 744 days.

The plea deal requires Murdaugh to fully cooperate with prosecutors, pay restitution and take a lie detector test if requested. He will be sentenced at a later date.

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"The Defendant agrees to be fully truthful and forthright with federal, state and local law enforcement agencies by providing full, complete and truthful information about all criminal activities about which he/she has knowledge," according to the plea agreement he signed Monday.

Alex Murdaugh wearing yellow prison-issue jumpsuit in courtroom sketch.

A sketch of Alex Murdaugh pleading guilty Thursday to 22 financial crimes in South Carolina federal court. (Rob Maniscalco for Fox News Digital)

If Murdaugh follows through on his end, prosecutors will ask the judge to impose a prison term that will run at the same time as any sentence imposed in state court for similar crimes.

The federal counts, for which he faces a maximum of 30 years, are based on the same financial misdeeds he's accused of in a slew of state indictments. And he's scheduled to go to trial in November on some of those charges.

Murdaugh's alleged co-conspirators, ex-attorney Cory Fleming and former Palmetto State Bank CEO Russell Laffitte, have already been sentenced for their roles in the schemes.

Alex Murdaugh arrives in court in Beaufort

Alex Murdaugh arrives in court in Beaufort, S.C., on Sept. 14, 2023. Murdaugh appeared publicly as a convicted murderer for the first time at the state court hearing regarding the slew of financial crimes allegedly committed by the disbarred attorney.  (AP Photo/James Pollard)

The plea comes one day after the hit Netflix series "Murdaugh Murders: A Southern Scandal" dropped season two, featuring a bombshell claim from the disgraced lawyer's alleged cohort, Curtis Eddie Smith.

Mudaugh allegedly asked Smith, a former client, to shoot him in the head three months after the murders of Maggie and Paul so his eldest son, Buster Murdaugh, could collect $10 million in life insurance payouts. 

Smith, 62, said he asked Murdaugh why he wanted to die. 

murdaugh associate curtis eddie smith in court

Curtis "Cousin Eddie" Smith, 62, is taken back to jail after a judge revoked his bond at a hearing in the Richland County Courthouse in Columbia, S.C., on Aug. 11, 2022. (Tracy Glantz/The State/Tribune News Service via Getty Images)

"Because they’re going to be able to prove that I’m responsible for Maggie and Paul," Murdaugh allegedly replied, referring to the South Carolina Law Enforcement Division (SLED), which was probing the double murder.

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Smith said he immediately refused. "That ain’t happening. Not today, not tomorrow. It ain’t happening," he recalled telling Murdaugh. 

After the bizarre conversation, Smith said he was concerned about Murdaugh and followed him. The attorney pulled over on the side of a rural road in Hampton County on April 4, 2021, and Smith also stopped.

"When I pulled up there, and I rolled the window down, he’s coming up to my window with a gun," Smith claimed. 

Smith said he fired his own gun in the air to scare Murdaugh, who dropped to the ground and scraped his head. The bullet didn't graze Murdaugh's head, Smith insisted.

Smith fled, and Murdaugh called 911, falsely claiming an unknown assailant shot him while he tried to change a flat tire. He was taken to the hospital and treated for a bullet graze.

Murdaugh has previously admitted he asked his friend to kill him as part of a botched insurance fraud scheme.

READ ALEX MURDAUGH'S PLEA AGREEMENT

In FOX Nation's documentary "The Fall of the House of Murdaugh," which aired earlier this month, Buster exclusively told Martha MacCallum his father didn't receive a fair trial.

"I think it was a tilted table from the beginning," he told MacCallum. "And I think, unfortunately, a lot of the jurors felt that way prior to when they had to deliberate. It was predetermined in their minds, prior to when they ever heard any shred of evidence that was given in that room."

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Murdaugh's lawyers have filed a motion for a new trial based on allegations court clerk Becky Hill tampered with jurors during the double murder trial in Colleton County.