Having an episode banned from airing is a fairly common phenomenon in the world of television, and as times change so do the reasons why episodes are yanked.
Usually it's the network censors who pull an episode, such as Fox's censors refusing to air the Family Guy episode "Partial Terms Of Endearment" because it features Lois deciding whether or not to have an abortion.
But sometimes the show's creators make the decision to pull the episode due to tragic events that have taken place around the time the episode was supposed to air.
Hannibal creator Bryan Fuller ran into this problem with episode 4, which featured Molly Shannon as a psycho who brainwashes kids into killing other kids.
The episode was set to air soon after the Sandy Hook Elementary School shooting, so rather than risking the home audience "have a negative experience" while watching the show he opted to skip the episode.
We recently shared a mental_floss article from a few years ago featuring 27 temporarily banned TV episodes, and now they're back with a new collection of 26 Previously Banned TV Episodes You Can Stream Right Now that features a few repeats and a bunch of new entries worth checking out.