Top Dog introduces us to Lucca K458, a decorated and highly skilled military working dog. An extraordinary bond developed between Lucca and Marine Corps handler Chris Willingham, launching what became a legendary 400-mission career. Lucca belongs to an elite group trained to work off- leash at long distances from her handler. She and Willingham became so sought-after that units scheduled missions around their availability. The book describes, in gritty detail, their adventures , including tense, lifesaving explosive finds and rooftop firefights.