QI XL Season 4 is excellent tv show from 2003. I will grant that my expectations were very low before watching QI XL Season 4. Before you read this review and before I spoil you the story, watch the tv show, I highly recommend it. Anyway, this genre may boast of one of the larger number of titles. What determines the phenomenon of this tv show? It's realism, taking care of psychological probability?. You can watch the tv show online here or download it.