10 Exact Moments That Killed TV Shows

8. Deb Catches Dexter Killing - Dexter

The first four seasons of Dexter were magnificent television, and many fans still contend that the show should've concluded with its season four finale, which shockingly killed off Dex's (Michael C. Hall) wife Rita (Julie Benz) in fittingly circuitous fashion.

The show limped along for four more seasons before finally stumbling to a clumsy and unsatisfying close, but the moment that truly painted the writers into a corner came a good while prior.

In the season six finale, Dex's sister Deb (Jennifer Carpenter) not only realises she's in love with her foster brother, but then catches him in the act of killing.

It was certainly a ballsy move to have Deb finally discover the truth, yet the writers ultimately did nothing particularly interesting or plausible with it, given their clear aversion to either having Dex die or end up in handcuffs.

Instead, it led to Deb's character being assassinated over the course of the next two seasons, joining Dex in some murder, briefly becoming a drug addict and then dying of a stroke in the series finale.

Many will point to the infamous "Dex becomes a lumberjack" ending as the point that truly killed the show, but it had clearly run out of steam long before that, and it all began when the writers committed to a through-line they clearly had no idea how to execute.