This 200th episode of Law & Order is set in motion when a professor of philosophy is pushed in front of a subway train. Investigating the murder, detectives Briscoe (Jerry Orbach) and Curtis (Benjamin Bratt) must deal with a wily suspect (Jay O. Sanders) who changed his identity and place of residence after a bitter divorce and child-custody battle. Can the key to the mystery be found with the suspect's ex-wife, or with the children he "appropriated" before taking flight? ~ Hal Erickson, Rovi