NCIS: Los Angeles's Kensi Blye has seen the face of the White Ghost and it's most definitely not Agent Sabatino.

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Instead, the White Ghost (played by Matthew Del Negro) appears to be someone Kensi (Daniela Ruah) is quite familiar with - someone she appears reluctant to kill. Could the CBS drama be using the killer as a way to introduce Blye's ex-fiancée Jack?

Little is known about Kensi's former Marine beau outside of the fact that he served in Fallujah, suffered from PTSD, and walked out on her one Christmas morning. First mentioned during season 2, Jack was mostly forgotten about until series creator Shane Brennan hinted that the soldier might return during season 5.

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"Yes," Brennan said when TV Line asked if Jack would make an appearance, adding, "I answered you pretty quickly, so perhaps it's something we are already thinking about."

While there has been no official confirmation regarding Jack's involvement, Del Negro did not dismiss the notion when fans tweeted him about it after "Fish Out of Water" aired. Instead, the Teen Wolf actor retweeted several statements that implied his character was romantically involved with Kensi.

Do you think Jack is the White Ghost? Tell us in the poll below.

NCIS: LA airs Tuesdays at 9 p.m. ET on CBS. Click the video below to see a preview of the series' most recent episode, "Fish Out of Water."

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