Old Man's War is a military science fiction novel written by John Scalzi. It is set in a future where humanity has expanded into space and is engaged in a series of interstellar wars. The story follows John Perry, a 75-year-old man who enlists in the Colonial Defense Forces, a military organization that recruits senior citizens to fight against alien species. As John undergoes a process that rejuvenates his body, he finds himself thrust into a brutal and deadly conflict. Old Man's War is a fast-paced and action-packed novel that explores themes of aging, identity, and the cost of war.
