Law & Order: Criminal Intent (2001)

S5E26 Moment of Truth (2)

Sully deceives everyone about his activities, but the reality is eventually revealed. Meanwhile, Cloud Dancing escapes to the Tongue River Valley. Sgt. McKay spots Sully at the location of the incident. Once Sgt. O'Connor learns the truth, he pursues Sully. The two engage in a heated confrontation, which ends with both of them tumbling over a cliff.