The chapter opens with a description of a cell called the "NK" cell, which is a natural killer cell. The cell is responsible for destroying foreign organisms, such as viruses and bacteria, that enter the human body. It is also responsible for protecting the body from infection. The chapter begins with a discussion of the role of the NK cell in killing foreign organisms. The white blood cell is the most important cell in the body because it destroys foreign invaders. The other cell, the neutrophil, is the second most important because it protects the body against infection. It also protects the immune system from foreign invaders by destroying foreign cells. The two cells discuss how they can use their experience to destroy foreign invaders in the future. The neutrophil says that they can now use their knowledge of killing foreign invaders to protect the body. He then tells the lactic acid bacterium that they have no worries about it. The lactic acid bacteria are good for human health because they support the body's immune system. The boss asks the cell if he can remember the enemy, and the cell says that he can. He tells the boss not to try to boost his confidence by attacking the killer cell, as it might look as if it is true, but really it is not. He also tells the cell that it is time for him to return to work, as the bacterial attacks on the body are too much. He warns the cell not to bump into him, as they are supposed to be loners. He says they should stop beating each other before they fight each other, as this will make them enemies.