Kathe E. Mazur

A young boy needs a heart transplant but doesn't seem to want it, and his treatment causes Burke and Yang to have philosophical differences. Meanwhile, when the interns rally to help Alex prepare to re-take his exam, Meredith has to remind Izzie of the true spirit of the Christmas holiday; and despite a reconciliation with his wife, Derek isn't in a festive mood.

Lisbon takes another look at the murky world of billionaire businessman Tommy Volker, as well as helping Jane to catch the killer of an up-and-coming model.

Frasier vows revenge after Bulldog plays a prank on him, and Daphne's mum wages war against a scorned trick-or-treater in a practical joke grudge match.

Addison falls for a colleague at St Ambrose. Elsewhere, Pete and Sheldon convince Violet to take a pregnancy test.

The murder of a petty officer sparks a lead in a 40-year-old airport bombing cold case that Gibbs and DiNozzo have been assigned to for the past two years. Also, McGee is jealous that he was not previously briefed on the cold case.

The team are called to Arizona to investigate a series of codes left by a suspect following two brutal murders.