Doctor Who is a series that is no stranger to retcons and plot holes thanks to several decades of wibbly-wobbly time traveling shenanigans. That being said, there’s one issue that not only affects the plot, but also completely contradicts the rules set up by the show.

In the 2005 Series 1 episode “Father’s Day,” the Doctor and his companion Rose Tyler travel back to the day Rose’s father died. Rose saves his life, creating a paradox. This summons pterodactyl-like creatures called “Reapers.” The Reapers attempt to treat the wound in time and space by consuming everyone in it. Rose’s father eventually repairs the wound by ensuring his own demise, which forces the Reapers away, but this episode cements the Reapers as a serious threat and they’re never seen or mentioned ever again. 

It’s almost as if everyone working on the show forgot that the Reapers were even introduced. Introducing a threat that’s caused by paradoxes in a series centered around time travel is a big deal. This is something that should be looming over the rest of the series. The risk of causing a paradox has immense stakes because of the Reapers, but those stakes are completely gone if the Reapers never appear again.

Various paradoxes have happened throughout the series since they were introduced and yet they never reared their ugly heads again. It’s understandable for the writers to not want to use them since they’d potentially limit stories they want to create, but the Reapers were never even written out. They’re just ignored. It definitely benefits the writing process to not use them, but why even introduce them in the first place?

The episode that featured them was during its first series after being rebooted in 2005, so it was during a time when they were finding their footing. It may have been a good idea to use these Reapers at first, but it definitely makes sense to do away with them for the sake of writing fun stories. That being said, there should have been a stated reason why they’ve been absent since. Otherwise, this forgotten rule feels like a massive plot hole.

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