Guest Appearances

President Bartlet's injury leaves Chief of Staff McGarry to face multiple crises, and Sam accidentally spends the night with a call girl.

Seaborn ignores warnings from co-workers and pursues a relationship with a call girl, and CJ involves herself in a public dispute between the president and vice president.

The president and first lady host a tense dinner at the White House, a hurricane heads towards an American naval fleet, and a group of survivalists tests the president.

As the president leaves the White House to do some Christmas shopping, Toby finds out about a war hero who died alone, and a persistent reporter begins to win over CJ for a date.

The president awaits the results of a popularity poll, and Sam is photographed as he gives a graduation gift to a known call girl.

The 126 crew respond to a military tank on the loose in downtown Austin and a human pile-up at the roller derby; a new paramedic captain joins the team; Owen is reunited with his ex-wife.

Olivia finds herself in the middle of a media storm, but this time she's on the opposing side of the Oval Office when Fitz's pick for Supreme Court Justice is caught in a torrid affair with Liv's new client, CEO Sarah Stanner.

Castle and the boys, along with a new NYPD detective, Sullivan, investigate the murder of a former child star. The case takes a turn for the worse when Beckett and McCord arrive.

Beckett and Castle face the consequences of their actions during a high-stakes investigation.

After a volcanic eruption wreaks havoc in Austin, the members of the 126 race to save lives at a college pool party.

Owen and T.K. risk their lives to save two brothers trapped in a homemade minefield; Grace receives an emergency call from a conjoined twin whose brother is dying; Tommy interviews new candidates to fill the team's open position.

Grace is caught in the ice storm as she goes into labour, and Judd, Owen and Tommy race to find her.

The 126 is on the scene when a disastrous wedding comes crumbling down; Grace helps a dominatrix and her slave involved in a shocking situation; Owen and Gwyneth struggle to label their new relationship.

A funeral where another dead body crashes the burial; an MRI goes haywire; Owen and Tommy each feel displaced in their homes.

Judd is shocked at the latest victim of an emergency call; Grace and Carlos must save a woman literally trapped in a domestic abuse situation; a horrific motorway crash threatens the lives of a father and daughter.

A bank robbery, an apartment fire and a pregnant woman lost in a parking garage are the seemingly unconnected calls to which the 126 responds; Carlos finds himself working on a case with his Texas Ranger father.

A medieval-themed restaurant suffers a case of carbon monoxide poisoning; the crew worry that Paul still has not mentally recovered from his surgery; Mateo's old fire captain offers him a promotion.

Beckett races to find a stolen toxin capable of killing thousands of people, and Castle has less than 24 hours to live after being exposed to the chemical weapon.

As the unexpected arctic cold front and ice storm continue to cause havoc in Austin, Owen works to rescue the lives of the stranded migrants; T.K.'s life hangs in the balance; Grace prepares for the birth of her baby.

TK's mother has an emergency, so Owen and TK travel to New York on a flight that has a mechanical failure; TK reflects on when Gwyn helped get him into rehab years ago.