Star Trek: The Next Generation — Episode 3: Elementary, Dear Data

You are watching the episode Elementary, Dear Data Stardate: 42286.3. Data and Geordi become involved with a holodeck program about Sherlock Holmes and his investigations, when they create Sherlock's arch nemesis, Moriarty; however, modifications to the Moriarty character include the capability of out-smarting Data, which leads to some unexpected consequences.