TV Shows That Went Downhill After Season 1
13. 'Heroes' (2006-'10)
Heroes was a breakout hit well before the Marvel Cinematic Universe took over. The superhero series, which follows normal people who discover they have dormant abilities, gained fans largely thanks to its talented young cast — Zachary Quinto, Milo Ventimiglia, and Hayden Panettiere. However, the series dropped off in quality significantly after the mystery of Season 1. Creator Tim Kring even apologized to fans for the weak second season. You don't see that very often.