Professor Hans de Jaberwocky is holding the world to ransom, either give him £100,000,000, twenty BMX Bikes and a bucket of shiny pebbles (his favourite food) or he will activate seven Doomsday Devices which will wipe out the unprotected human race and turn them into gunge. It is up to S1021/K0987 (nickname Psycho), a Mega-Battle Droid, to find all seven devices over seven levels and destroy their power supply. Call Me Psycho is a side view flick screen run 'n gun shooter with some platform elements where you control Psycho and you must get from the left of each level to the right searching for each Doomsday Device. As you move through each level their are various enemies with various weapons that will try to stop you and you must avoid or shoot them with one of four types of weapons, a pistol, bazooka, M-16 or a Flamethrower, each with limited ammo. You start with just the pistol but the other weapons can be collected on the way as well as ammo for each weapon. There are also various obstacles like rockets, tanks and planes that cannot be touched and platforms and barrels are used to jump over them. If you touch an obstacle, or are shot or touched by the enemy then you lose part of a energy gauge and when it runs out then you lose one of three lives but there is food that can be collected to top the gauge up. Once you find a device then you must shoot the power supply to switch it off and then you find a submarine to take you to the next level. If you reach the submarine without switching of the power supply then you have to start the level again.