Everything-everywhere’s Gary Arndt joins Paul and Elizabeth to reveal the identity of Jack the Ripper. Many suspects were considered at the time of these gruesome murders in 1888 in London, but no one was ever convicted of the crimes. Now, DNA evidence suggests the killer’s identity, says Gary, who also reports on the Great London Beer Flood of 1814. Plus: What’s the world’s smallest country? And what’s the solution to the Monty Hall Problem? Tune in to learn more.