Who was behind a failed rocket launch?
That was revealed on NCIS: Los Angeles Season 9 Episode 20 as Callen, Sam and Nell ventured into the Angeles Forest to search for the parts of it.
However, the mission took a dangerous turn when it emerged that there was a top-secret government device.
Meanwhile, Hetty tried to help Keane acclimate to life in the states, but did her plan emerge as a success?
Use the video above to watch NCIS: Los Angeles online right here via TV Fanatic.
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Paul Dailly is the Associate Editor for TV Fanatic. Follow him on Twitter.