SEASON FINALE: Part 1 of 2. Another Idol season has come and almost gone. Tonight is the one-hour performance part of the two-part finale, with the only singers left standing, Caleb Johnson and Jena Irene, competing for honors as the Season 13 winner. For one of them, 13 will be a lucky number. For Fox, which continues to watch ratings slide lower and lower season after season, not so much.