Trial By Robot is the 36th produced episode and the 29th Broadcast episode of the series Fireball XL5
Robots have vanished from several planets. The only clue seems to be that Professor Himber, the greatest robot scientist in the Universe, gave a lecture when the robots were taken. After Himber has left Space City, Robert the Robot takes off in Fireball XL1. They follow him to planet 82, were they are captured and tried by Himber for damaging an inhabitant of Robotvia. Their robot jurors find them guilty. Professor Matic is able to retune Robert and the Prosecutor Robot and after a battle with the robots, take Himber back to Earth.
- Zero reveals that the forth robot disappeared on May 27th and it is now August. It takes the XL5 crew three months to travel to Planet 82 (or Robotvia as it is renamed by Himber), so it is November when they arrive and will be February by the time they return to Earth.