Watch Free Online HD Moviesjoy. The legend of Ali Baba and the forty thieves: Ali Baba discovers a hidden cave where a band of thieves have stored their enormous treasure. Cassim also learns about the cave, but he is caught by the thieves and put to death. Knowing that their secret has been found out, the thieves devise a trick in an attempt to kill Ali Baba and anyone else who might know about their hiding place.