Who and why brutally killed a promising young woman—right after a party she threw? Many are absolutely convinced that the killer is her boyfriend: jealous, domineering, with serious self-control problems. But he screams loudly about his innocence, and evidence of his guilt isn’t obvious. An accidental witness to the crime might help find the guilty one. However, this witness is unusual: he tells only the pure truth because he simply can’t lie—but he speaks in a way that makes it extremely difficult to reconstruct the full picture…