A Texas actress who played a zombie on the TV show "The Walking Dead" has struck a plea deal with federal prosecutors after being accused of trying to frame her husband for sending poison letters to President Obama and New York Mayor Michael R. Bloomberg.
Prosecutors filed notice in federal court in east Texas Thursday that Shannon Guess Richardson, 35, had accepted a deal.
In addition to a small part in "The Walking Dead," Richardson had minor roles in "The Vampire Diaries" and "The Blind Side," according to her profile in the movie database IMDb.
The investigation began in May after Obama, Bloomberg and Mark Glaze -- director of the Bloomberg-backed Mayors Against Illegal Guns group -- received letters containing the poison known as ricin, accompanied by a typed threat:
"You will have to kill me and my family before you get my guns," read the notes sent to Bloomberg and Glaze. "Anyone wants to come to my house will get shot in the face. The right to bear arms is my constitutional God given right and I will excersice [sic] that right til the day I die."
In a similar note to Obama, the sender alluded to having a wife and kids. After news of the poison letters broke, Richardson approached investigators to tell them that her husband had sent them.
Richardson's husband, Nathaniel David Richardson, denied involvement and said she was trying to end their marriage. Investigators turned their attention to the actress.
According to an affidavit filed by an FBI agent, Shannon Richardson failed a lie-detector test in a second interview and began to adjust her story -- now saying that she'd known her husband had sent the letters and had planted evidence of the poison on his things so he'd get caught.
Even stranger, a computer that the couple turned over to investigators showed that someone had searched for information about the Tupelo, Miss., ricin case, which had played out in national headlines a month earlier.
In the Tupelo case, an Elvis impersonator was initially arrested on suspicion of sending ricin-laced letters to the president and other officials before investigators let him go and arrested his rival, a taekwondo instructor, on suspicion of framing him. (Last week, officials unveiled new allegations that the jailed taekwondo instructor had kept trying to frame the Elvis impersonator even from behind bars.)
Whether the Tupelo case served as inspiration was unclear, but the outcomes were the same: Shannon Richardson, not her husband, was indicted for the poisoning attempts.
Investigators found that some computer files associated with the poison mailings had been accessed from the couple's home while Nathaniel Richardson was at work. On the day before Shannon Richardson's June arrest, she told investigators she had helped send the letters because her husband had forced her.
"I had theories [that] she wanted to get her face out there, and she wanted to destroy me," Nathaniel Richardson, who was not charged in the case, told ABC News in an interview conducted with his attorney. "She wanted to be an actress, she really did."
Shannon Richardson's attorney told ABC News on Saturday that she had agreed to admit to her role in the plot in exchange for a sentence not to exceed 18 years in prison.
Ricin, which occurs naturally in castor beans, can take several forms and is potentially fatal when inhaled or ingested. There is no antidote.