10 TV Shows Ruined By One Dumb Decision

3. Sherlock - Bringing Sherlock Back (Without A Proper Explanation)

Sherlock started out as a fiendishly clever re-imagining of Arthur Conan Doyle's works, transplanting the detective into a modern setting with a lot of visual pizzaz, sharp wit, and excellent lead performances from Benedict Cumberbatch and Martin Freeman. For its first six episodes - three released in 2010, another three in 2012 - it was perhaps the best of British TV at that time.

And then came the fall.

The Reichenbach Fall itself is one of Sherlock's best episodes - a dazzling, daring entry that ramps up the battle between Holmes and Moriarty to shocking new levels - but it's what comes after that ruins it. The show returns with little to no real explanation of how Sherlock actually survived, instead content to thumb its nose at viewers and the many fan theories that had sprung up.

From there things would only get worse: a swerve into comedy followed, and then in Season 4 we got a series of increasingly convoluted plot points that became ridiculous to the point of parody, mixed with some James Bond-esque action for Mary Watson, and the show isn't likely to return anytime soon, if ever. That downward turn, however, is rooted in that decision to bring Sherlock back - and more so how they did it - with the show going from clever but knowing to creators Steven Moffat and Mark Gatiss disappearing up their own backsides.