The Mysterious Cities of Gold (1982)

S1E5 The Abduction of Zia

Following a perilous adventure, Esteban and his companions find themselves stranded on an enigmatic island. As night falls, a cloaked figure approaches them stealthily. Without making a sound, the figure pilfers a map and a firearm before abducting Zia. Determined, Esteban takes off in pursuit. He soon stumbles upon an intriguing treehouse, where he finds Zia held captive. To his astonishment, the elusive shadow reveals itself to be a kind-hearted boy named Tao, who is the same age as Esteban.