An attempt to provide Data with a challenging Sherlock Holmes holodeck RPG scenario backfires when its Prof. Moriarty character accidentally becomes self-aware.



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Episode complete credited cast:
Lt. Commander Data / Sherlock Holmes
Wesley Crusher (credit only)
Biff Manard ...
Diz White ...
Ensign Clancy (as Anne Elizabeth Ramsay)
Richard Merson ...
Pie Man


When the Enterprise arrives a few days early at its rendezvous point to meet the USS Victory, the crew have a bit of leisure time on their hands. For Data and Geordi Laforge, it means a trip to the holodeck and 221B Baker St. With Data in the role of Holmes and Laforge as Dr. Watson, they take on a challenge from Dr. Pulaski that Data couldn't solve a genuine mystery. Data has a bit of time adjusting to a real mystery - as opposed to one for which he knows the outcome. In giving the holodeck computer its instructions however, Geordi's specifications for an opponent results in a far superior creation than expected putting them and the entire ship in danger. Written by garykmcd

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Release Date:

3 December 1988 (USA)  »

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Sound Mix:


Aspect Ratio:

1.33 : 1
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Did You Know?


This takes place in the late 19th century and 2365. See more »


When La Forge is theorizing on the murder victim's demise, the police inspector squats down, resting his right hand on his right knee. But in the next shot, his right arm is on his right knee. See more »


Commander William T. Riker: [to Worf, who is dressed in a 19th-century suit] You'd be a big hit in London.
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Referenced in Star Trek: The Next Generation: Ship in a Bottle (1993) See more »


Star Trek: The Next Generation Main Title
Composed by Jerry Goldsmith and Alexander Courage
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User Reviews

In response to Qanqor
18 August 2016 | by See all my reviews

This was a really good episode. Everything about it was fun and exciting. I think Qanqor's review of this episode implies that he missed the point of what it was supposed to be. There needed to be an episode that wasn't so dark. They had just lost Yar.

Also no. The computer was locked out by Moriarity himself. When the system created him, it created him to be smart enough to defeat Data. The computer gace Moriarity the knowledge of the entire ship. Along with any knowledge that was present in the system itself. He overrode the system.(You honestly would have known that if you got halfway through. And at the end, he is the one that cancels the override)

And no. They could not have destroyed the Holodeck, they had explained that doing so would destroy Palaski.

Despite all those things. Even if they could just destroy the holodeck. The whole purpose of the episode was to solve a mystery. It was to challenge one's mind. Not use brute force to accomplish something.

4 of 4 people found this review helpful.  Was this review helpful to you?

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