There is a frenzy in a scientific research center. Darting leptons, deadly sub-atomic particles, are running free in laboratory rooms, and it is your job to capture them using a robot craft with gameplay similar to Qix. Ion trails left behind by your craft while it is in a free area are used to enclose the area to capture the lepton or render the area safe from leptons. The area can be enclosed when you reach the edge of the room or safety area. Until then, while your craft is in free area, both the trail and the craft are vulnerable from a lepton hit. Later laboratory rooms developed dangerous charged omega particles which move along the ion trails and should be avoided as well. The craft can surf along the edge of the room or safety area using the navigational keys. It is moved into the free area with the spacebar at half speed. Pressing the spacebar again produces full speed movement. Points are scored for the areas made safe with slow-drawn areas worth double the point of the fast-drawn ones. Each room has a base score which is doubled if a lepton is captured and this multiplies the area scores. There is a time bonus if the room can be cleared quickly. The laboratory room is declared safe when all the free leptons are captured or 95% of the free area has been safely enclosed. An extra craft is available after the 3rd, 6th, and 9th rooms. The top ten scores are stored in a high score table.