Castle and Beckett find themselves on opposite sides of the case when Castle's old school friend emerges as the prime suspect in his own wife's murder. As they work to solve the crime, Castle comes to realize that one of two terrible things must be true... Either Detective Beckett is about to arrest an innocent man for murder, or his old friend is a cold-blooded killer.
- Directed by
- John Terlesky
- Written by
- Moira Kirland
Guest stars
All episodes — Season 3
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S3 E1A Deadly Affair
Sep 20, 20107.944 min
When Beckett and her team burst into an apartment on a murderer's trail, they see Castle standing over a dead woman's body holding a gun; Beckett arrests Castle as he asserts his innocence.
S3 E2He's Dead, She's Dead
Sep 27, 20107.644 min
Beckett and Castle search for a psychic's killer while debating the existence of extrasensory abilities.
S3 E3Under the Gun
Oct 4, 20107.744 min
When a coded document attracts Castle's attention, Beckett must steer the case back to the violent felons who populated their victim's world; when Beckett's ex-partner arrives, Castle must watch the relationship become romantic.
S3 E4Punked
Oct 11, 20107.944 min
Castle and Beckett look into the murder of a young mathematician gunned down with a 200-year-old bullet, sparking some wild theories by Castle about a time-traveling killer. When their investigation uncovers a tricked-out DeLorean and a sus
S3 E5Anatomy of a Murder
Oct 18, 20107.844 min
An unknown woman falls out of a casket along with the original deceased when pallbearers lose control of the casket at a funeral; the investigation takes Beckett and Castle into the world of amorous, bed-hopping physicians.
S3 E63XK
Oct 25, 2010844 min
When a beautiful woman is found dead in an alley, all clues point to her being a victim of the notorious Triple Killer. The Triple Killer, or 3XK, terrorized New York City four years ago, then mysteriously disappeared. Now he's back. In a d