The Sherlocks returned on Tuesday's episode of NCIS, and they have a new probie in their ranks: Tony DiNozzo Sr. (Robert Wagner).

Of course, Dr. James Palmer (Brian Dietzen) is also a member of the Sherlocks now, and he almost immediately breaks the first rule of the Sherlocks by spilling the beans to the rest of the team about DiNozzo Sr.'s involvement.

Gibbs (Mark Harmon) is less than thrilled when the Sherlocks stick their noses in the case of the week, especially when it comes to Judith (Jessica Walter), who continues to shamelessly flirt with him. DiNozzo Sr. picks up on his son's former mentor's displeasure, and tries to smooth things over by explaining the roots of his involvement. He tells Gibbs he went to visit Tony and little Tali in Paris over Christmas, and when he "fell into a funk" upon returning to the States, it was Tony who suggested that his dad join the Sherlocks to snap out of it.

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But Senior's detective skills aren't that sharp — he assumes that Gibbs and Judith were once an item, and asks Gibbs for his blessing to woo her, which is pretty gross. Gibbs also finds this disgusting, but mostly because he's insulted by the idea of dating the lascivious Judith.

As it turns out, though, it's DiNozzo Sr. and his Sherlocks counterparts who help Gibbs and Co. solve the case, resulting in them arresting a man who was caught in a love triangle for murdering his wife. DiNozzo gets rewarded for his efforts by becoming a full-fledged member of the Sherlocks. And to celebrate, he's going to take Judith to Paris to meet his daughter and granddaughter. Will NCIS rely more on his services when he returns?

NCIS airs Tuesdays at 8/7c on CBS.

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