Actor Allusion: Frank's mention of being a Marine with service in Vietnam. During Magnum, P.I.'s run, Tom Selleck often wore a cap with the legend "VMO-2", which was a Marine Forward Air Control squadron out of Da Nang.
Real-Life Relative: Jack and Sean Reagan, Danny's two boys are played by real-life brothers Tony and Andrew Terraciano.
You Might Remember Me from...: Tom Selleck's role as Police Commissioner Frank Reagan is his first major role in quite a while, apart from a string of TV movies based on the Jesse Stone book series. He mentioned in an interview on The Talk that he took the job partly because the script made him cry.