The Fourth Season curse is formerly great shows that should have ended after the 3rd season, because the 4th and subsequent seasons were a trainwreck of appallingly bad ‘we don’t know what to do anymore!’ writing.
HELL ON WHEELS – Those first two seasons are tremendous. Season 3 begins to lose me with the very unlikeable arc they put Common’S character on, and 4th season with the plodding Amish arc and the unwatchable Common episodes, it is television at its worst.
BEING HUMAN (UK) – After 3 strong seasons ending in a cliffhanger, its obvious the writers wrote themselves into a corner they were incapable of writing themselves out of. Seasons 4 and 5 are apallingly inept and poorly concieved.
PENNY DREADFUL – While this show didn’t make it to a 4th season, it seems to have had its awful seasson one season early. Seasonn 1 was magnificent, season 2 floundered at the end, with the unnecessary noble savage sacrificing himself for no good reason, and the horrendous, pouffant/twilight/boy band -makeup on the Werewolf, and season three ran with all these flaws, feeling rushed and uninspired.