Complete story — includes the ending
With the NYPD no longer employing him, Sherlock persuades FBI agent Gary Burke to hire him and Joan. They investigate a triple homicide at a neuroeconomics research facility, but chafe under Burke's close supervision. The researchers were working on a brainwashing technique for DARPA. All the hard drives containing the research were stolen. They meet DARPA Deputy Director Meher and Special Projects leader Alta Von See. It turns out that the researchers realised that their method did not work at all. Von See would be in line to succeed Meher. Von See used another device developed at DARPA, a sonic pressure shield, to incapacitate the victims, then shot them at her leisure. A pet lab rat died at the same time as the victims, also from the shield's effects. A streak of rubber from the base of her crutch by the device's storage closet implicates Von See. Morland offers to reinstate him and Joan at the NYPD. Sherlock eventually decides to take his father's offer, but Joan discovers that Morland bribed the DA into dropping the charges, and she warns him that she will not let him hurt Sherlock.
Sources and content license
Source and revision history · Adapted from Wikipedia contributors, List of Elementary episodes. HTML formatting and reference markers removed. · Content license