One of us is lying

The story says there were six people... one of them died... four accused... and the last outside the circle of suspicion. Is the killer one of these individuals? Each of them has a reason that drives him to commit the crime. The victim revealed the secret before he died, saying that the first uses performance-enhancing drugs, and the second is a drug dealer, and the third is a cheater contrary to what he claims, and the fourth is a traitor. Is the killer one of these or another person who has a vested interest in what is happening? And what role does the police play in stirring suspicion among the suspects? Are the police methods professional? Or are they trying to cover up the investigation and accuse the person who is the weakest link? A story where one of us is lying, written by Karen M. MacManus for fans of suspense, investigation, mystery, and surprises. A story whose secret will only be discovered before the end by the clever readers.