The nineteenth-century frontier town of a holodeck Western programme, which turned dangerous in 2369 when its characters began taking on Data's face and abilities.
Deadwood is the setting of the Ancient West holodeck programme in the Next Generation episode A Fistful of Datas.
Alexander persuades his father Worf to play the sheriff of Deadwood, with himself as deputy and Deanna Troi as a mysterious gunslinger. Their job is to hold the outlaw Eli Hollander in jail until the marshal arrives.
Meanwhile an experiment linking Data to the ship's computer goes wrong. The holodeck safeties fail and the characters, starting with Eli's father Frank Hollander, appear with Data's features and his speed and strength. Worf has to play the story to its end, using a makeshift personal force field to survive the final showdown.