The theme of the game will be that of a robber escaping the police where the player is the robber. The player has to get from one end of the room to another without being caught by the two policemen. The policemen will be going around the width of the play space continuously (black arrowed lines in my drawing) at two points of the play space.

The player starts from a safe zone at the top (green area) where the police cannot spot him. As soon as he crossed the first wall, the police can spot the player unless the player is on the other side of a wall from the police.The player can move up, down, left or right using the keyboard. In my rough sketch attached, I have made boxes for both the policemen (red boxes) which indicate their field of vision at different points of their path depending on the position of the wall relative to their position. If the policemen and the player are in the same box at any point, the player will be caught. The player will get three lives and on being caught for the third time, the game will restart.

Potential additions: the safe zones at the top, bottom and middle will be green in colour for the player to know. The field of vision of the policemen will be highlighted as they are moving. I am not sure if I will be able to incorporate these into my game but they will make the play experience much better so I will try my best to add these extra features.