Gregory Jbara as Deputy Commissioner of Public Information Garrett Moore, Robert Clohessy as Lt. Sidney Gormley, and Abigail Hawk as Detective Abigail Baker, Frank's primary aide, appear regularly and receive "special guest star" billing.

After getting a match for an unknown first cousin from a DNA network, Sean Reagan does some detective work to figure out who this mystery person might be.

Frank gets a request from a woman, Paula Hill (Bonnie Somerville) to transfer her son (Will Hochman), a detective in firearms, to a safer assignment.

She tells Frank not to contact either of them again, but Joe and Sean get in touch, and the former joins the family for Sunday dinner.

They attempt to find the mother, who had panicked after two members of an infant trafficking ring (posing as adoption lawyers) sought her baby, leaving him at the steps of the precinct in hopes of protecting him.