A Quiet Place and A Quiet Place Part II both find humanity plagued by alien monsters, but each movie has revealed some of their key weaknesses/

The alien creatures of A Quiet Place and A Quiet Place Part II are incredibly strong and deadly, but the monsters do have a few confirmed weaknesses. Since the shocking first appearance of one of the monsters in A Quiet Place's opening scene, which resulted in the death of Beau Abbott (Cade Woodward), the creatures have been shown to plague humanity in the franchise. Fast, powerful, and extremely difficult to kill, they're an almost unbeatable foe for humanity to face. Almost.

Neither A Quiet Place nor A Quiet Place 2 delves too far into the origins of the alien monsters, and the sense of mystique only adds to their fear factor. But some reveals have been made, such as showing that the aliens arrived on Earth via several meteors, including one that landed at least somewhat close to the New England town the Abbotts called home. Both movies are about their attempts at survival, but also shift into fighting back.

The aliens have impenetrable skin and hyper-sensitive hearing, which makes them incredibly tough, but they have some weaknesses too. A Quiet Place has the Abbotts learning how to kill one monster, while A Quiet Place 2 ends with the discovery of how to take down lots of them. Here's every weakness the alien monsters have.

The Monsters Are Susceptible To High Frequency & Feedback

One of the monsters' greatest strengths is their incredible hearing. As shown in both A Quiet Place and A Quiet Place Part II, the monsters are able to pick up on even the smallest, briefest of sounds from a considerable distance, but that also becomes a weakness. Because their hearing is so sensitive, then it also means they're susceptible to incredibly high frequencies and audio feedback, as seen when Regan (Millicent Simmonds) uses her hearing aid against them. Even to a regular person feedback isn't a comfortable sound, so it's no surprise that it's even worse to a creature with much greater sensitivity. The feedback and frequency stops the aliens in their tracks, and at a high enough pitch - as seen via Regan's hearing aid - it will make them expose their skin, and can also cause them to collapse.

Water Is A Key Weakness For A Quiet Place's Monsters

A Quiet Place hinted at the creatures' weakness to water, with Lee (John Krasinski) and Marcus (Noah Jupe) having a conversation behind a waterfall so that they could speak freely, and Evelyn (Emily Blunt) also using water to move around and avoid detection. That trick is used again in A Quiet Place 2, when the monsters invade Emmett's (Cillian Murphy) bunker and Evelyn uses the sprinkler to confuse them. Because of their super hearing, the water drowns out and overrides everything else around them, but that's not the only way it's a weakness. A Quiet Place 2 reveals an island community who escaped on boats, confirming that the monsters can't swim. A monster still makes it to the island thanks to a boat and some luck, but drowning the creatures, or just escaping across water, is a way of killing or avoiding them.

The Alien Monsters' Heads Are Their Only Weak Spots

The alien monsters have astonishingly strong skin; not only is it resistant to bullets, but given they arrived on meteors and defeated the US military, then there's seemingly very little that could even leave a scratch on them. The only weakness they have in terms of their bodies is their skin underneath their armor, which can only be seen - and attacked - when they open up their heads to expose it. The frequency and feedback is the best way to make them do that, and once it is then they're much more susceptible to regular weapons. Not only are they killed with bullets in both A Quiet Place and A Quiet Place Part II, but the latter also has Regan killing one by stabbing it with a pole, suggesting any reasonably strong material is enough to kill them this way. As the fight against the monsters continues, then A Quiet Place 3 could reveal even more of their weaknesses.

Next: A Quiet Place 3 Will Struggle To Repeat Part 2's John Krasinski Trick