In 2368 the Enterprise-D rescued a young Borg drone, named Hugh, whose growing individuality led Picard to cancel a plan to use him as a weapon.
In 2368 the Enterprise-D found the wreck of a Borg scout ship with a single injured survivor and took him aboard. Starfleet saw a chance to plant a program in the drone that could spread through the Collective and destroy it. Geordi La Forge treated the drone, who was named Hugh, and the two became friends.
As Hugh began to think of himself as an individual, Picard decided that using him as a weapon would be wrong. Hugh chose to return to the Borg so that his rescuers would be safe, carrying his new sense of self back to the Collective.