A scientist mysteriously builds strange structures including a giant automatic pistol and a bow and arrow but won't tell anybody the reason. (They're for two giants who want to fight each other)
Mark and Elsa meet a Professor Volo who has a claims to have a camera that sees the future. Mark scoffs at the idea and accuses the Prof of perpetuating a hoax. So Volo sics a big monster on them. After that the story gets really complicated.