He's a protector first and an avenger second.
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As one of NCIS: Los Angeles' top special agents, G Callen is a man of many talents. One week, he's chasing after bad guys and saving the day; the next, he's going deep undercover to solve an international mystery. Whatever the case, he's ready and able for anything! Let's take a look at some of Callen's most action-packed moments in the field.