Hypnotic Sphere is the 2nd produced and 37th broadcast episode of British television series Fireball XL5.
Fuel Tankers from the planet Earth continue to disappear in space. When Fireball Xl5 goes to investigate, they come across a hypnotic sphere. In Fireball XL5, Professor Matic spots a lone satellite on the map. As they get closer they discover it’s a fuel tanker from Earth. Steve Zodiac tries to contact the tanker, but gets no reply. When they arrive at the tanker Steve and Professor Matic go across to it by using the thrusters packs. When they’re on board they discover the pilot of the tanker alive but in a state of hypnosis. They arrive back on earth and explain to Commander Zero what they discovered. He tells them, that this is the fourth incident that has happened of the past few weeks Steve comes up with a plan. In space Fireball XL5 is escorting a different fuel tanker with a pilot on board (Joe), on the same route the other tankers took. During the journey they come across spherical craft directly in front of them. As they go past it, the sphere starts to glow. Very slowly they all start to feel tired. A voice on the speakers tells Steve to change their course and land on planet Suventa . However, he tries to fight the hypnotic sphere and tells Robert the Robot to continue on course. Soon, everyone besides Robert has passed out and the fuel tanker pilot has obeyed the sphere and headed to the planet. Fireball XL5, however is heading for the fiery planet of Mirana, since Robert is staying on the current course. Just before they hit the planet surface, Steve wakes up and manages to pull Fireball out of the collision. Venus and Matic wake up wondering what happened. Matic, knowing that Robert records everything he hears, suggests playing it back. They listen and discover that the spheres glowing causes the hypnosis and the voice is just a command. They then decide to return to the sight where the sphere appeared. They cover all the windows on Fireball XL5 so they wont be hypnotised again. When the sphere arrives, they all pretend to be hypnotised. Steve lands the ship at the destination that the voice tells him to. When they land, they are instructed to enter a room in a small base on the planet. Inside the room is a brain inside a glass container. They discover that the Brain wanted to use the fuel, which would power thirty more spheres. Then they would go out and hypnotise the universe and the brain would become in charge of everything. Steve stops pretending to be hypnotised and kills the brain by destroying the heat system, causing the brain to freeze to death.
- How did the brain know that Steve's second name was Zodiac?