Whether you’re a fan of regency romances like Bridgerton or fantasy dramas such as The Witcher, we all love a binge worthy TV series! But sometimes TV shows go several seasons past their peak and ratings plummet by the final season.
With this in mind, RANT Casino analysed every episode rating from popular TV shows over the past 5-10 years, to discover which series took the biggest downward turn from their pilot episodes.
TV Series that passed their peak
| TV Series | Duration | Pilot episode IMDb rating /10 | Most recent episode IMDb rating /10 | *Average rating decline per episode |
| Westworld | 2016-2022 | 8.8 | 7.0 | -0.028 |
| Game of Thrones | 2011-2019 | 8.9 | 4.0 | -0.014 |
| The Crown | 2016-ongoing | 8.2 | 7.4 | -0.012 |
*Rating decline figure based on the average decline in episode ratings across the whole series
Please find the complete data here.
1. Westworld
Peak episode: 1×10 – The Bicameral Mind
Worst rated episode: 4×08 – Que Será, Será
RANT Casino can reveal that Westworld is the TV series that took the biggest downturn in ratings over time. Set in a Wild West themed amusement park within a dystopian world, the series pilot aired with an IMDb rating of 8.8/10. However, across all four seasons the episode’s ratings declined at a rate of -0.028 per episode.
The final installment, Season 4, Episode 8, titled Que Será, Será, is the show’s lowest rated episode at 7.0/10. With the season one finale (S1, E10), The Bicameral Mind, rated as the series peak episode, with an audience/IMDB rating of 9.7/10.
- Game of Thrones
Peak episode: 3×09 – The Rains of Castamere
Worst rated episode: 8×06 – The Iron Throne
Ranking in second is Game of Thrones. With a fantasy backdrop of dragons and warfare over the Iron throne, this series saw a total of eight seasons; with the initial episode receiving a high rating of 8.9/10 from reviewers. As the TV adaptation moved away from the plot of the ‘A Song of Ice and Fire’ book series around season 5, it saw the ratings plummet.
The final episode, The Iron Throne, was the lowest rated episode across the whole series (4/10). Although receiving the largest IMDb rating drop (4.9) from the first episode to the last, the series overall downward trend stands at -0.014, with several highly rated episodes throughout.
Season 3, Episode 9 The Rains of Castamere, is also touted as one of the show’s most memorable episodes. As Game of Thrones peak episode, it rated a whopping 9.9/ 10.
- The Crown
Peak episode: 3×03 – Aberfan
Worst rated episode: 5×10 – Decommissioned
Based on the reign of Queen Elizabeth II, The Crown comes in third. The pilot episode received an IMDb rating of 8.2/10; compared to its most recent (and worst rated) episode to date, S5 E10, Decommissioned at 7.4/10. The average downward rating trend of the series stands at –0.012 but with one final season yet to come, there is still a hope for a turnaround.
The Crowns peak episode, Aberfan, episode 3 of season 3 saw its highest rating of 9.3/10 – which sees tragedy strike in the Welsh town of Aberfan, based on true events.
Methodology:
- RANT Casino sought to find out which TV series got better and which got worse with time.
- A comprehensive seed list of 14 popular series from the past 5-10 years was compiled utilising IMDb and Reddit.
- Following this, the ratings for each episode were scraped from IMDb.
- For each show, the 3-episode moving average was calculated as the average of the previous three episodes. This was used to determine where a show ‘peaks’ and where it ‘falls’.
- Additionally, the moving-average delta was calculated as the difference between each 3-episode moving average.
- An average rating for each season was also calculated for all shows and a formula was used, where if the trend was > 0.01 the show got better over time, if it was < -0.01 it got worse, otherwise stayed the same.
- This data was updated June 2023 and is subject to change.
Hannah@journalistic.org