An elderly Japanese man gets brutally beaten after going fishing. He slashed one attacker with his fishing knife. Craig Tanaka is a Vietnam War veteran and his son Jack is a LAPD detective. Sam and Fatima debate whether this is a hate crime. Kilbride tells Roundtree that he requested this case from SecNav because of how his best friend's Japanese family was treated during World War II. Jack is adamant that the attack is a hate crime. Captain Carlos Fuentes testifies to all that Tanaka did as a volunteer at the weapons museum. Tanaka had been doing carpentry work on the side. Deeks and Kensi think the attack might be premeditated. Sam and Callen check the diner Tanaka was renovating. They find the message "Go home, Jap" in red painted over on a wall. An artist in a wheelchair had recovered a can of red spray paint nearby. It has fingerprints from Jason Quinn, who lives with Billy Strauss, whose family used to own the bankrupt diner.Deeks and Kensi discuss what race of child they would be willing to adopt. Kensi and Deeks cut off the fleeing Quinn. Sam and Callen find Strauss's home trashed. Quinn said a cop was breaking into their house and he ran. Quinn denied participating in the attack on Tanaka. Jack is suspected of taking Strauss. LAPD Detective Matt Guerraro, a friend of Jack's, had checked with the crime lab's records on the fingerprints. Jack took Strauss and his dad, who planned the assault. Guerraro tells them where to find Jack. They arrest Jack and the Strausses. Kilbride goes with Jack to the hospital to visit Craig. Jack posted a video of the Strausses' confessions to social media, even though it means sacrificing his career. Craig wakes up. Jack introduces him to Kilbride.