Michelle's name has to be cleared by Sean when she is called in and questioned over the attempted assissantion of a diplomat that she had once protected. The two's investigation soon uncovers a huge cover up that needs to be exposed.
The son of one of Sean's old colleagues commits suicide. However the death is suspicious and leads to King and Maxwell opening up a unexpected case which involves a targeted serial killer who's after the family of former agents.
King and Maxwell are hired to locate a stolen cell phone but discover that there's much more at stake after a sleazy lawyer tries to force them off the case. Meanwhile, Sean receives some interesting information regarding the Ritter assassination.
When the key witness to a company's deadly chemical spill is murdered inside FBI headquarters, King and Maxwell are trapped in the building. With a killer on the loose and Special Agent Rigby's career on the line, they have only hours to solve the murder and find a new witness to testify at a Senate hearing to bring the company to justice.
Sean's investigation of the Ritter assassination threatens to end his partnership with Michelle as she considers returning to the Secret Service. The shocking truth sends Sean back to the scene of the crime to prevent history from repeating itself.