A Satarran scheme to end a long war by erasing the memories of the Enterprise-D's crew and persuading them that their mission was to destroy the Lysian Central Command.
In The Next Generation episode Conundrum, an unknown ship scans the Enterprise-D with a beam that wipes every personal memory aboard while leaving skills intact. Nobody knows their name or rank; Worf at first assumes command. When the computer is partly restored it lists a crew that includes a first officer, Commander Kieran MacDuff, a man nobody has reason to doubt.
The altered records say the Federation is at war with the Lysian Alliance and that the ship must cross the border under radio silence and destroy the enemy's command centre. The Enterprise brushes aside Lysian ships that are no match for it, which troubles Picard.
At the lightly armed station, with thousands aboard, Picard refuses to fire. MacDuff tries to take over and is stunned, revealing himself as a Satarran, whose people have fought the Lysians for decades. Memories are restored, and Picard apologises to the Lysians.