LOS ANGELES (CNN) – The “NCIS” lab has lost its goth genius. Pauley Perrette, who played forensic scientist Abby Sciuto, has signed off from the long-running CBS crime drama after 15 seasons on the show.

Perrette’s exit from the series was announced in October 2017, however, her character’s fate was left in question at the end of last week’s episode, after she and MI-6 officer Clayton Reeves (played by Duane Henry), were confronted by a gun-wielding thief.

SPOILERS FOR THE MAY 8 EPISODE TO FOLLOW

At the beginning of Tuesday night’s episode, viewers learned that Abby was in serious condition and suffered a pierced artery after being shot in the chest. Reeves, meanwhile, died from his injuries.

Abby’s co-workers stayed on the case as she struggled to come out of a coma, learning that Abby was targeted by a person who she had helped put behind bars years ago. When Abby awoke, she helped them crack the case further, leading them directly to the person responsible, a man named Robert King — an antagonist from a previous season.

King was put back behind bars — this time sporting a broken nose thanks to unit leader Leroy Jethro Gibbs (Mark Harmon).

Pauley Perrette "NCIS"

(credit: CBS)

Abby then told her co-workers that she intended leave NCIS to carry through the philanthropic aspirations of Reeves, who had died trying to save her. “Clay died saving my life, and I owe him a debt and I intend to see it through,” she stated. “Clay always wanted to start a charity in honor of his mom and, since he’s not here to make that happen, I will.”

“I know you may not understand, but it’s something I have to do,” Abby added, “and not just for him, but for me.”

Gibbs, whom Abby saw as a father figure, was not around for her announcement, so she told him in a letter. “I hope you know what you mean to me, Gibbs — every moment, every lesson, every hug, I’m thankful for it all,” she wrote.

Now that Perrette has left the show, the only original cast members who remain are Harmon, David McCallum, Sean Murray and Brian Dietzen, with the latter two serving in a recurring capacity in the earlier seasons.

Perrette’s current and former co-stars marked the character’s final episode with a series of tributes on social media.

Perrette’s own closing thoughts seem to have been best summed up by her character, who also told her co-workers, “You have to go with your gut, and my gut is telling me I have to go.”

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