A visitor from Latvia causes Charles and Jake to investigate Nikolaj's family. Holt and Amy bring in famed forensic scientist Dr. Yee to help close a case for Rosa.
Jake and Gina attend their 20th high school reunion. Charles helps Rosa with her love life.
Jake and Charles investigate a case of Hitchcock and Scully's from the 1980s. Amy's uniformed officers and Terry's detectives fight over limited resources.
Jake and Amy go on their honeymoon. Capt. Holt finds out whether he is the new commissioner of the NYPD.