After a mass murder at an Internet security company, evidence indicates that the person responsible is not a typical serial killer; Prentiss is required to complete recertification training.

Everyone's lives on Wisteria Lane are forever changed when a hostage situation occurs at a local supermarket.

Susan professes her love for Ian while Gaby and Carlos try to rekindle their love, and Bree is confronted with Orson's past.

The Enterprise becomes ensnared in a temporal disturbance from which there seems little hope of escape without destroying the ship and crew.

Torres and Lightman question a former gang leader who claims to be rehabilitated; Loker and Foster look into the death of a firefighter who was killed in the line of duty.

Cyrus hopes to recruit an influential power couple (Mary McCormack and Josh Randall) during preparations for the State of the Union; Mellie's struggle gets the nation's attention.

Beckett races against time to find a stolen toxin capable of killing thousands. To make matters worse, Castle gets exposed to it.

Kira's assignment to evacuate a stubborn Bajoran from a moon about to be drained of its energy forces her to evaluate her priorities.

Alan finds himself pitted against Jerry in the case of a woman suing a department store for selling "pornographic" dolls to children; Shirley and Paul must decide Denny's fate when he makes a politically incorrect comment.

A psychic's husband's death sparks discussion of Fisher & Sons.

While investigating an elderly woman's murder, Grissom receives a miniature crime scene replica; Greg attends a hearing to ascertain his culpability in a teenager's accidental death.

The doctors face a tough decision regarding the future of Oceanside Wellness; a new admirer offers Addison a tempting proposition; Charlotte receives a case that hits close to home.

Lilly reopens the 2006 case of a college-bound man's disappearance after his sister finds an Internet video of him in the underground subculture of bare-knuckle brawling.

Cooper and Charlotte second-guess their wedding plans; an investigator visits the practice to question the doctors about Violet's case.

Being forced to reveal the truth about his illness leaves Walt facing the prospect of how to pay for an expensive series of cancer treatments.

As Walt’s medical bills and domestic problems mount, Jesse will only agree to get back into the drug business if he can dictate the terms.

Bobby and the assistant district attorney face off over an assisted suicide; Eugene helps Lindsay defend an aged bookie.

Walt tries to bring his family back together; with Saul's help, Jesse makes an unexpected investment.

A woman sues a beverage manufacturer for the death of her son due to alcoholism; Ellenor tries to stop the execution of a mentally ill woman.

Ellenor fights to stop the execution of a mentally ill woman (Alfre Woodard); the firm is torn over a settlement with an alcohol company.