Major plot hole: If NASA was ready to hire Cooper as the pilot for their most important spaceflight mission of all-time after he found their secret base by accident, why did they never thought about recruiting him before? He lives on a farm a few blocks away from your base god dammit, and you seem to have completely dismissed the other pilot that would have made the mission in his place, so clearly you thought Cooper was SO GOOD that he would be better than him after a 1-day crash-course on the new mission. So why didn’t you recruit him months before that? He was more likely to say yes if you give him more than a few hours’ notice to say farewell to his children.
Major Plot hole: If a blight on Earth causes most crops to die and significantly reduce the available food sources for humanity, the later fact that humanity can grow food in space stations without any blight is a logical sign that they could all grow the same food on earth in green houses for a lot less money. So they never had to leave Earth after Murph found the formulas. Good job.
Super Plot hole: What’s that? Time travel you say Chris Nolan? Let’s see if it completely destroys your great movie’s narrative. Here’s an important word for everyone who writes time-travel stories: causality. Future humans cannot create a wormhole to save their ancestors because their ancestors did not survive to make them able to create wormhole technology in the first place. It doesn’t work in Terminator, it doesn’t work in Harry Potter, it doesn’t work in X-MEN, and it won’t work here either because it is the same time paradox. You can’t save your past-self if your past-self dies without the intervention of the future you because the future you simply never existed. (I swear it makes total sense when you read that sentence a second time). And if future humans somehow exist without having saved the past humans…why save them in the first place?
Super Plot hole: Or just for fun, let’s be nice and pretend the future humans can help the present humans in order to save themselves: in other words, let’s pretend there is no time paradox. Why create a wormhole around Saturn in order to get Cooper to survive tidal waves and a crazy Matt Damon to finally fall in a black hole so that he can text his daughter a few important pages of math equations in Morse code by punching gravity into her watch….instead of simply giving the math equations themselves in Morse code…..at any point in history like let’s say around the time crops started to die?
Unaddressed Issue: If the 3 alien planets on the other side of the wormhole orbit a black hole and not a star that orbits around a black hole, where do they get their source of light? On each of these planets, the scenes take place during day-time and yet the black hole should absorb most light-sources around them. So what’s up with that?
Unaddressed Issue: The title of the movie is wrong. Interstellar means travel between stars inside the same galaxy. In this movie, Cooper, his bland human companions and kick-ass awesome robots are travelling across galaxies in a wormhole, so the movie should be called: Intergalactic. Did they keep Interstellar because it sounds cooler and less nerdy?