DAY 3

Detective Beckett then forcefully interviews Whittaker and discovers the artwork of Sword of Lone Vengeance at his apartment. Whittaker then states that Lone Vengeance is supposed to stamp out crime and was not real. However, Detective Beckett stated that Whittaker had been mugged previously and he had been non-compliant for the police interview. Castle implies that that was the turning point in his life when he had donned the costume of Lone Vengeance. 

Detective Beckett offers a deal to place him in segregated confinement should he confess to the crime. Whittaker then hesitantly confesses that he murdered the victim because he had discovered his identity. Castle states that a superhero has a code and if he or she should go and break it, the event would trigger a crisis of fate which would devastate the superhero. Castle then asks Whittaker’s feelings regarding the murder who then replies that he had only felt really bad about it. Detective Beckett then asks why Whittaker had chopped off the victim’s hand after he killed him which was a rouse to try and figure out if he had been lying to which he replied he did not know. Both her and Castle believe that Whittaker is covering for someone and discover that the vigilante could be hiding at an abandoned tenant building where Whittaker had been mugged and where Chad had found Lone Vengeance which only proves that that was the place where the vigilante would be hiding.

Castle and Detective Beckett then infiltrate the hideout and discover various samurai swords through a hidden door. Detective Espesito radios in and states that he had seen an unknown person climb up the fire exit. Detective Beckett managed to catch Lone Vengeance off-guard and orders the vigilante to remove the mask and discovers that it was actually Officer Hastings, a police officer at the NYPD. During the interrogation, Hastings revealed that the reason why she had turned to a vigilante was because her father was murdered and decided to take justice into her own hands. 

Castle discovers that the reason Whittaker confessed was because he had loved Hastings and tried to protect her. Hastings denied that she murdered the victim and explained that she had stolen the knuckle piece was not hers and took it to test it for fingerprints. She said that the victim was a creature of habit and that the killer knew that the victim would end up in the alley. Detective Beckett believes that Hastings is innocent and that there is another person impersonating Lone Vengeance. Castle and Beckett decide that the killer was someone who knew the victim and who had experience in wielding swords. 

They arrive at the conclusion that Tony, the first suspect, was the real culprit. During the interrogation, they press Tony for answers that he had impersonated Lone Vengeance in order to point them in the wrong direction and to stop the real vigilante from interrupting his criminal business. Although Tony denied the charges, Detective Beckett showed him the knuckle plates which were found to have fingerprints belonging to Tony’s cousin Ernesto who confessed to making the outfit for Tony. 

So Tony Valtini was the murderer.