An attempt by a gang of thieves to steal trilithium resin from the Enterprise-D's engines while the ship was evacuated for a baryon sweep, foiled single-handedly by Picard.
In The Next Generation episode Starship Mine, the Enterprise-D is emptied at the Remmler Array above Arkaria Base so that a lethal sweep can clear accumulated baryon particles. The senior staff attend a dull reception given by the base commander, Hutchinson. Picard slips back for his saddle and finds strangers at work in the corridors.
They are thieves led by a woman named Kelsey, draining trilithium resin, a toxic by-product of the warp engines that can be made into a weapon. Picard passes himself off as Mot the barber, escapes and fights a running battle through the ship, moving ahead of the advancing sweep. On the base, accomplices take the officers hostage and Hutchinson is killed; Data and La Forge improvise a way to stun the captors.
Kelsey reaches her ship with the resin, but Picard has taken the control rod from its container, and her vessel explodes.