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 cast overview:
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?


At the begining of the episode when Geordi shows Data the model of the sailing ship Victory, the flags displayed on the model seem to be nonsensical. The flags read P0M P3K P3M P3X UJC K0P P (the next two flags aren't in the international code) UPX XK PU. It seems as though the flags were chosen based on how they looked, and not by what they mean. See more »


Data, as Holmes, takes Whittaker's Almanac off the shelve and returns it backwards, pages facing out, instead of the title. Data does everything as precisely as possible, so he would have put the book back correctly. 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 End Credits
Composed by Jerry Goldsmith and Alexander Courage
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User Reviews

One step closer to the TNG we know and love
1 May 2016 | by (United States) – See all my reviews

'Elementary, Dear Data' may be a holodeck episode (and I honestly didn't expect all that much walking in), but it's one that refreshingly sees TNG up its game. This time around, it's Data and Geordi in a Sherlock Holmes mystery and Moriarty winds up taking over the ship. Not complicated, but I did like the big question being asked here: can a computer be alive? Dr. Pulaski spends a good deal of time haranguing Data for not being able to reason like real people (geez, this woman), while Moriarty yearns to learn more about the ship, stretch beyond his simulation limits and (more importantly) doesn't want his program being erased. But the situation is handled more thoughtfully than expected with Capt. Picard (in sweet top hat) brokering an understanding between the two.

All in all, a great episode; the wardrobe and sets are well done and you can tell Brent Spiner loves this Holmes stuff. More importantly, this actually feels like TNG: the characters feel right, Picard's actually softening, and everything's clicking.


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