This is a game based on the popular Doctor Who TV show. You are The Doctor and must destroy all the Daleks before they get to you. Each level has progrssively more Daleks.
There are two ways to destroy the Daleks. Make them run into each other, or use a Sonic Screwdriver. When two or more Daleks collide, they create a pile of debris, this pile will destroy any other Dalek that runs into it. The Sonic Screwdriver can be used 3 times to make any Dalek directly next to you disappear.