Yes, the Pope who came immediately after Pope John XXIII lasted only a few weeks. He died mysteriously. The machinations of the Vatican have always been covert ... and the politics internecine. Although no one knows, there has been much speculation that he did not die naturally.
(Denny Crane: "Sometimes you can only look for answers from God and failing that... and Fox News".)
Actually, the successor to John XXIII (Paul VI) served from '63 to '78.
It was John-Paul I who died only a month or so after being elected in '78.
John-Paul II is his successor.