The Three Investigators

Three kid detectives go on an epic journey to eerie Skeleton Island. Once home to pirates, it's now plagued by a mysterious beast.

Jupiter Jones refuses to attend the surprise party his friends throw against his expressed wished. However he loves investigating an intruder, who gets away but without the clue he came looking for. It leads to another Californian ghost town and its "castle's" secret, which links to orphan Jupiter's parents.