Great TV series are known for their unexpected plot twists, but often, writers struggle with where to take the show next. Few would argue that Game of Thrones began its decline after Jon Snow’s 'death', but plenty of other shows experienced even more drastic downfalls.
5. Once Upon a Time – A Disastrous Encounter with Frozen
The early seasons of Once Upon a Time kept viewers intrigued with bold reinterpretations of classic fairy tales. However, in Season 3, the show attempted to integrate characters from Frozen. While Elsa and Anna’s popularity should have guaranteed success, the writers failed to weave them seamlessly into the existing story. As a result, the series lost its magic, and viewers lost interest.
4. Glee – The Breakup of Finn and Rachel
Finn and Rachel’s relationship was one of Glee's central storylines, and their wedding was meant to be an emotional climax. However, their sudden breakup in Season 3 marked a turning point. Attempts to replace departing characters with new students felt forced, and the show lost its original charm and cohesion.
3. The Flash – Iris’s Disappearance

For years, The Flash thrived on strong characters and well-developed villains. However, Season 6 took a downturn when Iris suddenly vanished, leading to a convoluted and unengaging storyline. Instead of a gripping drama, audiences were left with a drawn-out and meaningless arc that drained the show of its original energy.
2. One Tree Hill – The Car Crash That Killed the Drama
This iconic teen drama thrived on complex yet relatable character relationships. However, the Season 3 finale, featuring a character’s car accident, failed to bring the expected emotional impact. Instead, it diminished audience investment, and the following seasons struggled to recapture the same intensity and realism.
1. Sherlock – Holmes’s Fake Death
Sherlock’s apparent death at the end of Season 2 seemed like the perfect way to conclude his story. However, the writers decided to pull off yet another 'brilliant' trick by making him fake his own demise. His return felt contrived, undermining the carefully crafted suspense. From that point on, Sherlock spiraled into chaotic and overcomplicated storytelling, losing its once impeccable logic and style.