Hugh, formerly Third of Five, was a former Borg drone rescued by the USS Enterprise-D in 2368 in the Argolis Cluster. Critically injured at the time, Dr. Crusher brought him back to the Enterprise for treatment. While there, he began to make friends with Geordi La Forge, who named him "Hugh" (a mispronunciation of the word "you").
When Hugh met Jean-Luc Picard, who was wary of having Hugh on board the ship, Hugh recognized him as Locutus, and informed him that he had learned that resistance was not futile, stating that he (and Hugh used the word I, his second use of a singular pronoun) would not assist in the assimilation of La Forge. Picard was stunned that a Borg drone would say such things, and Hugh was returned to where he was found to rejoin the Borg Collective.
This new sense of individuality proved deadly to the Collective, and his cube quickly fell into disarray and disconnected from the hive mind and drifted in space until 2370 when it was discovered by Lore. Lore assumed leadership over the group of drones, allowing them to remain as individuals, but ran tests on them, leaving them many with injuries. Hugh realized that Lore was a poor leader and led a rebellion against him.