The sneering nobleman of Q's Robin Hood fantasy, who holds Vash prisoner as Maid Marian in Nottingham Castle and intends to marry her or have her beheaded.
Sir Guy of Gisbourne is the antagonist of the scenario Q builds in the fourth-season episode Qpid, set in 2367. He is played by Clive Revill. Q himself takes the part of the Sheriff of Nottingham, leaving Sir Guy as the scenario's own creation.
In the story Sir Guy has Maid Marian, who is in fact the archaeologist Vash, locked in his castle and condemned to die unless she becomes his wife. Vash confounds both Q and Picard by accepting the proposal to save her neck, and then by betraying Picard when he climbs in to rescue her.
When the Enterprise officers, cast as the Merry Men, storm the castle on the day of the execution, Picard fights Sir Guy up and down the great staircase and runs him through, ending the game.