When the CSIs uncover a female victim on the Navarro estate that matches Esteban's MO, Vina Navarro, Esteban's grandmother, comes forward to help solve the case. However, things take a twist when the team also discovers the three-decade-old remains of a male victim, with evidence linking Diego to the murder. Before he can be arrested, Vina shoots Diego in what appears to be self-defense. Later, the team decodes a microchip disguised as a lollipop in Diego’s pocket, which leads them to Esteban's murder lair and the evidence needed to put him away for good. Finally, after learning her son will survive, Vina flees the country and Horatio realizes that Vina, not Diego, is the murderer of the male victim, who is later identified as Alfredo Navarro, Vina's long missing husband and Diego's father.