But short stories would prove to be the genre for which his contributions were most significant. The Pit and the Pendulum and The Tell-Tale Heart are two of his most enduring works. Poe virtually invented detective stories and the notion of focusing on the process of solving the crime, rather than the criminal or the act. He was notorious for writing tales told by "irresponsible narrators," whose self-deluding ways force the reader to take an active role in deciphering the mystery.