#LA’ — What Brings Nate Back? (PHOTOS)

In the March 13 episode, “All the Little Things,” CBS teases, he “meets with Admiral Kilbride [Gerald McRaney] and learns about the CIA project from the ’70s and ’80s involving children.” So might Special Agent G. Callen (Chris O’Donnell) be the reason Nate’s back now?

As you’ll recall, this season began with Callen digging into his past, breaking into Hetty Lange’s (Linda Hunt) files and finding one on Subject 17, who sounded a lot like him. He, like other foster kids, were put through cognitive tests, psychologically profiled and screened, like a junior version of the CIA’s selection process. Did Hetty run that program and know Callen much longer than he thought? She confirmed he was Subject 17. A flashback at the end of the premiere showed a younger Callen watching something on a projector, while he read his file: “The subject shows an exceptional memory. Given the proper opportunity and education, there’s no telling what he could achieve.”

When NCIS: LA premiered, Cambor was a series regular before he left in Season 2. He has since returned for quite a few guest spots, with his last coming in Season 8’s “Old Tricks.”

As for the case in this episode, when a newborn child is found abandoned on a Navy ship, Special Agent Kensi Blye (Daniela Ruah) and Investigator Marty Deeks (Eric Christian Olsen) look for a mother onboard a Navy ship before she dies of complications.

Scroll down for a look at “All the Little Things.”

NCIS: Los Angeles, Sundays, 9/8c, CBS