Clayton's Pirates are also known to be evil, nasty, greedy, selfish, arrogant, eccentric, persuasive, treacherous, vituperative, and short-tempered to their conceited leader, Clayton. They are basically hateful, ruthless, murderous, destructive, unscrupulous, inconsiderate, manipulative, egotistical, possessive, conniving, wrathful, violent, brutal, cruel, mean, livid, and sneaky, so they are able to capture Tarzan's ape family somewhere in the jungle.
Under the orders of the ship's captain, the Thugs are first seen packing up the luggage and supplies of Jane, Archimedes, and Cecil Clayton (much to the latter's dismay) onto the ship to return home to London. When Clayton manipulates Tarzan's feelings for Jane by telling him that she would stay in the Jungle with if he showed them the gorillas, Tarzan agrees. Clayton then informs Snipes (one of the Thugs) to gather the other pirates together for the next phase of his plan.
When Tarzan, Jane, and Archimedes boarded the ship the next day to return to England, Jane and her father are captured by the thugs (who have also turned on the captain and his officers); after seeing this, Tarzan tried to escape them by jumping on the cages and climbing the ship's masts.
Even though he almost effortlessly avoided them at first, the thugs quickly started catching up with him, with one of them grabbing him from his ankle. He shakes him off, but as they were closing in on him, he makes a huge leap from the top of the mast and manages to hold on to the funnel's end, only to fall down shortly afterwards. As Tarzan crawled out of the boxes' remnants, two of the thugs were quick enough to grab him and slam him against the wall of the superstructure; as Tarzan was still weak, pessimistic, and hurting after falling from such a height, he didn't have enough strength to break free from the thugs' grip. When Tarzan sees Clayton, he begs for his help while trying to break free from them, but Clayton reveals to him that he tricked him into leading them to the Gorillas' nests so that he and his pirates could capture them easily and sell them to a zoo in London.
After locking Tarzan in the ship's brig along with Jane, Archimedes, and the captain, Clayton and his pirates take a loading boat through a river into the jungle and ambush the gorillas, netting them, forcing them into cages, and throwing the babies in burlap sacks. Tarzan's ape father, Kerchak intervenes to rescue his group but is overpowered when the thugs restrain him with whips and a net.
Clayton slowly approaches Kerchak and prepares to kill him, preferring him to be stuffed before Tarzan, Jane, and Archimedes (who escaped from the ship's brig with Terk and Tantor's help) intervene and fight off Clayton's pirates, freeing the gorillas and putting the thugs in the cages that they used to confine the gorillas in. The thugs are not seen after this, so their fate is unknown, but it is likely that they were put in the ship's brig and taken back to England to await trial for their crime.