It was supposed to be another typical day at Canterlot High for Sunset Shimmer and her friends. Except they didn't expect to find a Marine Lance Corporal bleeding on the steps of their school. The resulting investigation leads the humane 7 to the NCIS team on the case, led by Leroy Jethro Gibbs...

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Attempted murder on a Marine Lance Corporal in suburban Massachusetts. That's what Gibbs and his team were told by Director Vance. Except he forgot to mention that the entire area of Canter City is a parallel to the realm of Equestria, accessible only though a mysterious portal on the grounds of the local high school.

As Gibbs and his team begin to unravel the case, reluctantly working with a CIA Agent liaison, they quickly realize that this attack was only the beginning of a cross-world terrorist plot, supported by both humans and ponies. And only the NCIS team can stop it in time...

...alongside several multicolored ponies and their human counterparts.
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NCIS Crossover, will have gore, swearing , violence, and plenty of Gibbs-trademark headslaps. Set in Season Four of Friendship is Magic.