Law & Order: Criminal Intent Episode 9.14 Palimpsest

PALMER ABRIGAILLE was a collector of rare books, an obsession which he clung to at the expense of all else. His estate had fallen into decline when a grifter named DYLAN WELD started to blackmail him over some ill-gotten books. When the money wasn't enough, Dylan set his eyes on LENORE, Palmer's daughter, a troubled young woman. This pushed Palmer to the breaking point.

One morning, Nichols and Stevens are called to the Abrigaille estate, where they find the bodies of Palmer and Dylan... apparent victims of an old fashioned duel. Nichols, who was once close to both Palmer and Lenore, believes the victims were killed by a third party and that the culprit is still in the house.

There is no shortage of suspects in the case. There's MERILL, Palmer's self-serving nephew, BERNARD & REGINA, a couple who shared Palmer's passion for books, and even RICHARD CELESTE, the faithful butler. Discovering the murderer will prove challenging, even for a detective of Nichols' caliber.