"The Echo Maker" is a novel by Richard Powers that explores themes of memory, identity, and the complexities of the human mind. The story follows Mark Schluter, a young man who suffers a traumatic brain injury in a car accident, leading to a rare condition called Capgras syndrome, where he believes his loved ones have been replaced by impostors. As Mark struggles to reconnect with his past and understand his new reality, his sister Pam becomes deeply involved in his recovery. The novel delves into the science of the brain and the emotional impact of loss, ultimately questioning what it means to truly know someone.