Oliver is concerned when a mysterious illness sweeps the city, infecting hundreds of people, including Diggle. Oliver discovers Vertigo in Diggle’s blood and realizes The Count has broken out of prison and is once again distributing his drug. Meanwhile, Moira goes on trial for her participation in the Undertaking. ADA Adam Donner collapses in court with Vertigo symptoms so Laurel must step in and try the case against Moira. Oliver is torn between standing by his family during the trial and catching The Count. However, things change when Felicity follows a lead and walks straight into a trap set by The Count.

The relationship between Rachel and Gene remains strained as Charlie shows her mom how much she’s grown. Meanwhile, Neville gives Jason a determined proclamation.

In the aftermath of the events chronicled in the film « Thor: The Dark World », Coulson and his team pick up the pieces – one of which threatens to destroy them.

Castle and Beckett arrive at a crime scene to discover that the female victim bears a shocking resemblance to Medical Examiner Lanie Parish. As the team tries to make sense of this mystery, they realize the killer may be targeting detectives of the 12th Precinct. Dr. Kelly Nieman, an exclusive Manhattan cosmetic surgeon who draws Castle and Beckett’s interest because of her connection to the victim.

When Barney’s father arrives at the hotel, Barney devises a plan that makes Robin very nervous. Meanwhile, Ted is convinced someone framed him by messing up a wedding-related duty.

Alicia must block the deportation of an undocumented immigrant who has been threatened by a cartel in Mexico. Eli’s reconnection with Natalie Flores concerns Marilyn. Robin tries to emulate Kalinda.

After new information comes to light, Carrie and Quinn pursue a key suspect in the Langley bombing. Saul deals with political backlash while Fara discovers the toll an intelligence job can take. Meanwhile, the Brody family gets startling news.

Following the shocking events at Jane’s house, the Red John list is narrowed down further, and the CBI’s priority is the remaining suspects.

When a beautiful young woman is murdered, Holmes and Watson investigate her ties to a billionaire CEO. Mycroft makes a case for Sherlock to move back to London.

Mellie is still trying to recover from the public backlash of the last year so she decides to do a hard-hitting news interview. Meanwhile, as Cyrus continues to plot against Sally Langston, we learn how Fitz, Mellie and Cyrus became a team. Back at OPA, Huck continues to push Quinn away, but Quinn’s bloodlust could get her into some dangerous situations.