Nichols reaches out to his father for assistance when he and Stevens are assigned the case of a real estate agent who has been murdered.

In the season finale of Criminal Intent… The body of a successful real estate agent is discovered in a basement, bled out. In order to understand the suspects, Nichols is forced to rely on an unlikely resource – his own father. Catch “Inhumane Society” followed by the season finale of Criminal Intent “Three-In-One.

Nichols has personal ties to a case when he investigates the murder of an old friend, an isolated book dealer with a troubled daught

A government official blackmails two doctors for overcharging patients before he is killed. The doctors have another secret to protect, however, and worry that someone will find out mobsters financed their practice.

The owner of a popular food truck is murdered, his body left for his fiancée to discover. What some dismiss as a simple street rivalry leads to a powerful political family who’ll do just about anything to maintain their dynasty.

The death of a student who was drained of blood leads the detectives to a cult in which followers believe they’re immortal and make use of blood dealers.

A new murder fits the style of a serial killer who was executed months earlier. Stevens must figure out if the killing is a copycat crime or if she helped convict an innocent man.

The murder of a magazine editor reveals his predilection for young girls, leaving Nichols and Stevens investigating not only his staff, but a Russian prostitution ring.

Four men who have been friends since high school discover they’re being blackmailed over the death of another childhood friend. When one of the four turns up dead, it’s up to Nichols and Stevens to uncover the truth behind a 22-year-old mystery.

A young girl from the midwest who moved to NYC, is murdered after visiting a medical center to receive treatment for an assault. Det. Nichols and Stevens must uncover the pysches of the killers before there is another murder.

A psychologist conducts unimaginable field experiments asking his human test subjects to make the impossible choice, but Detectives Nichols and Stevens are even more surprised by the man’s inspiration.

A body that’s been decapitated, initially thought to be a mob hit, leads Detectives Nichols and Stevens to an escort service and the financial would-be gods who utilize it.

Det. Nichols and Stevens investigate the death of a ballerina at a prestigious New York conservatory; a place where a love of art and beauty collides with the harsh reality of murder.

The murder of an NYPD detective brings Nichols and Stevens to a sleepy seaside town, ruled by one of Nichols’ old foes – an Irish mob boss with a reputation for eluding justice.