Summary

• Bo's eccentricity with water in Signs may have been due to real contamination, making the aliens weak to toxic water.
• Signs' aliens potentially represented inner demons, not weak to water but to holy water.
• Despite its flaws, Signs' emphasis on symbolism and character connections make it a rewatchable sci-fi horror film.

M. Night Shyamalan’s Signs is one of the most popular horror sci-fi movies but also one of the most divisive due to its water plot hole – and one theory solves this problem, but it also makes it worse. Shortly after the success of Unbreakable, Shyamalan returned with Signs, a sci-fi horror movie starring Mel Gibson as former Episcopal priest and now farmer Graham Hess and Joaquin Phoenix as his brother, Merrill Hess, a former baseball player. Graham lived with his son Morgan, daughter Bo, and Merrill, who moved in with them after the death of Graham’s wife.

The death of his wife led Graham to abandon his faith and become reclusive with his children, but an unexpected event led him to question everything. When large crop circles appeared on the farm, Graham initially suspected it was the work of vandals, but they soon learned it was the beginning of a worldwide alien invasion. Signs effectively built suspense from the beginning, but it crashed down with the nonsensical reveal that the aliens’ weakness was water. Now, a theory solves this huge plot hole in Signs, but at the same time, it makes it worse.

Signs Theory Suggests The Water Truly Was Contaminated

Bo Wasn’t Wrong About The Water

Signs showed the little eccentricities of the Hess family, particularly Bo’s, who never finished a glass of water because she always found something wrong with it.

Signs spent a good amount of its time showing the family dynamic at the Hess farm, with Merrill being close to Morgan and Bo, Morgan looking after his sister at all times, and Graham being quite distant with all of them as he continued to struggle with grief. Signs also showed the little eccentricities of the Hess family, particularly Bo’s, who never finished a glass of water because she always found something wrong with it, saying it was either contaminated or dirty. Because of this, Bo left half-full glasses of water all over the house.

Graham got the idea of the aliens possibly being weak to water after visiting Ray Reddy (Shyamalan), the man who killed his wife in a car accident. Reddy was preparing to leave his house after trapping an alien in the pantry, and he was moving near a lake as he believed aliens were avoiding water. Later, at the Hess’ house, the alien Reddy caught escaped and made it there, where, after spraying Morgan with a toxic gas, Merrill fought the alien with a baseball bat. During the fight, Merrill hit one of the glasses, realizing that water was, in fact, toxic to the aliens.

The theory explains Bo was always right and the water was indeed contaminated.

This revelation about water made no sense, as the aliens arrived at a planet made mostly of water, and if it was so toxic to them, they wouldn’t even have been able to come out of their ships without suffering some damage. Now, a theory shared on Reddit explains the water twist in Signs and solves its major plot hole, but it also makes it worse. The theory explains Bo was always right and the water was indeed contaminated, and while it wouldn’t have been deadly to humans, it definitely was to the aliens.

The author of the theory suggests that, because they were on a farm, the water could have contained pesticides, which Bo was sensitive enough to taste. The aliens might have avoided lakes because the groundwater was also contaminated, and following this logic, aliens probably wouldn’t have survived in big cities due to pollution. The theory solves the water plot hole and gives Bo’s eccentricity with water a bigger purpose, but it would be a very in-your-face explanation that ruins all the suspense and tension in Signs.

Signs’ Aliens Could Have Been Demons (& Were Defeated By Holy Water)

Signs Is Heavy On Religious Symbolism

Signs focused more on the family dynamics of the Hess than the aliens themselves.

This theory about the real weakness of the aliens in Signs and what was in the water connects to one of the most popular theories about the real nature of these creatures. Signs focused on a family in crisis after the death of the mother in an accident. This led to Graham’s loss of faith and a disconnection with his children, with Merrill trying to be the connecting link between all of them. The Hess family was forced to come together when the alien invasion began, finally being a family since the death of Graham’s wife.

Signs focused more on the family dynamics of the Hess than the aliens themselves, and their water weakness, inability to open doors (clearly, the alien in the pantry could have easily escaped but didn’t until much later), and the many biblical themes and imagery throughout the movie have led to the theory that the aliens were demons. The aliens/demons appeared when Graham itted to losing his faith, so they have been seen as the physical manifestation of his, Bo’s, Morgan’s, and Merrill’s inner demons, as they were all struggling with something at the time.

The theory adds that the aliens/demons weren’t weak towards water but holy water.

Signs was also heavy on religious symbolism and biblical references, most notably when the news announced that a solution to fighting the aliens had been found in “three small cities in the Middle East” and the Hess’ last supper. In line with this, the theory adds that the aliens/demons weren’t weak towards water but holy water – and as they were at the house of a (former) priest, the water in the house would technically be “holy water”, thus why the aliens/demons burned when in with it.

Signs Suggested Nothing Is A Coincidence (But The Water Twist Makes No Sense)

Everything Suddenly Makes Sense In The Third Act Of Signs

In addition to the family focus in Signs, the movie made it very clear that nothing is a coincidence – the characters spoke about it and the movie showed this through each character. Bo’s eccentricity with water was never explained, but it served a purpose as all those glasses all over the house were what allowed Merrill to kill the alien. Morgan had asthma, and he had an asthma attack while they hid in the basement that nearly killed him, but it was thanks to it that he wasn’t affected by the alien’s toxic gas.

If nothing was a coincidence in Signs, the water twist still makes no sense other than to give a purpose to Bo’s weird thing with water.

Merrill had a failed career as a baseball player, his bat hung from the wall in the living room at Graham’s house, and Graham’s wife’s last words for Merrill were to “swing away”. All these came together in the third act of Signs when Graham told Merrill to “swing away”, after which Merrill took the bat on the wall and fought the alien, breaking the glasses and beating the creature to death. However, if nothing was a coincidence in Signs, the water twist still makes no sense other than to give a purpose to Bo’s weird thing with water.

Despite its plot holes, nonsensical twists, and other flaws, Signs continues to be a must-watch of the sci-fi horror branch. Signs’ many symbolisms and different interpretations of the aliens and more make it one of the most rewatchable M. Night Shyamalan movies, even if the water twist continues to be one of the most controversial plot holes and twists of the 2000s.