First, let’s have a look at why this decision was important in the first place…

Quirinus Quirrell was a timid and nervous person, but he was also highly intelligent and gifted. At school he was most likely teased because of his shy nature and made to feel inadequate by others. To try and prove that he wasn’t a nobody, he developed an interest (theoretical at first) in the Dark Arts. That, coupled with his desire to make people take notice of him was what led him to seek out Voldemort.

However, Quirrell was immature, arrogant and underestimated Voldemort. He was no match for what remained of the Dark Lord and was possessed by him. While Quirrell still had his soul, he was weakened by having to share his body with an evil, more powerful one.

When Harry started his first term at Hogwarts, Quirrell was under this control. The famous turban he wore was to hide the monster that lurked underneath. Voldemort was looking for a way to return to power and had his sights set on the Philosopher’s Stone – which produced the Elixir of Life. If Voldemort had the Stone, he would be strong enough to create a body of his own and he would be immortal. Quirrell had already tried and failed to take it from Gringotts for him before term began. This attempt was noticed, and the Philosopher’s Stone was transported to Hogwarts for safekeeping.

This is where the troll came into play. Voldemort still wanted Quirrell to steal the Stone. To do that, Quirrell needed to have a proper look at what was guarding it on the third floor corridor. By letting the troll into the school, he caused a distraction and knew he would have time to investigate… he just didn’t foresee quite how pivotal that choice would be.

The troll in the dungeon set off a whole chain of events that were crucial to the first story. It added to Snape’s suspicions about Quirrell. It was what made Harry and Ron suspect Snape. It also led to the formation of the golden trio.

Without it, just how different would things have been? Would Hermione have ever become their friend? Would Voldemort have been able to achieve immortality? Most importantly, would Ron have ever been able to master Wingardium Leviosa?

Would Harry, Ron and Hermione have become friends?

The struggle between Harry, Ron, Hermione and the troll in the girls’ bathroom was a defining moment in Philosopher’s Stone. While Harry and Ron were already good friends, Hermione was not somebody they hung out with. Before this, they didn’t like her (Ron especially). They found her confidence and know-it-all tendencies to be rather jarring and it was Ron’s mean jibes that put her in the path of the troll in the first place.

After a Charms lesson, in which Hermione had thoroughly shown Ron up when it came to levitation, Ron vented his frustration by making nasty comments about her to Harry. Not only did he say she was a ‘nightmare’ but also said she had no friends. Hermione overheard them and ran to the girls’ bathroom crying – where she stayed all day. Now this day happened to be on Hallowe’en, the very same Hallowe’en that the troll entered the castle. In all the chaos, Harry realised Hermione would have had no idea about the danger she was in. They went to rescue her. Ron managed to pronounce Leviosa correctly. The troll was knocked out. Hermione covered for them. A bond was formed… and the rest was history.

If it wasn’t for the troll, there is the possibility that they wouldn’t have become friends. Without it, all that would have happened was Ron’s horrible comments and Hermione being very upset. It would be completely understandable that she would want nothing to do with the people who spoke about her behind her back. Rather than growing closer, this would have only pushed them further away from one another. While we reckon Harry and Ron would have felt some guilt about upsetting their classmate, we don’t think they would have been too fussed about not being her friend.

Although, that is not to say that they wouldn’t have become friends later. After all, they were always in close proximity to one another – being in the same year and house. While the troll acted as the catalyst to push them together, we can imagine them building a tentative bond more slowly over the course of their first year. Whether it was Harry or Ron sticking up for Hermione, or Hermione offering to help them with some tricky wand work in class, we think they would have got there eventually. They had more in common with each other than just defeating a troll… it feels wrong to reduce their entire friendship to just one moment.

Would Snape have realised what Quirrell was up to?

We think that Snape would have still figured out what Quirrell was up to without this incident. In fact, Quirrell told Harry that Snape had already begun to suspect him before Hallowe’en. So, when the troll was let into the dungeon, Snape already knew to head to the third floor to try and stop the Defence Against the Dark Arts teacher. However, at that point he had no solid evidence of what Quirrell was doing and was relying on his gut instinct (and a vague hint from Dumbledore) that he was doing something he shouldn’t.

Therefore, we think that the troll in the dungeon probably did more to push Snape towards confirming his theory rather than alerting him to Quirrell’s misdeeds in the first place. After that incident he was firmly on his radar. He even confronted Quirrell in the Forbidden Forest to try and discover just how close he was to stealing the Philosopher’s Stone.

Ultimately, if the troll hadn’t been let loose in Hogwarts, we think Snape may not have confirmed his suspicions about Quirrell so quickly. But we think he would have figured it out eventually – especially after the attempt on Harry’s life at the Quidditch match. Snape was intelligent and more than capable of piecing the puzzle together. As we learnt in Deathly Hallows, Dumbledore had asked him to ‘keep an eye on Quirrell’. With that request and the strange incidents that kept happening that year, it was only a matter of when Snape realised Quirrell’s true intentions and not if.

Would the golden trio still have suspected Snape?

This is a little trickier. On Hallowe’en, when Ron and Harry went to rescue Hermione, they saw Snape heading towards the third floor. At the moment, they were rather distracted with the dangerous business of a troll roaming the halls to pay too much attention, but they did spot him. They already knew that the third floor was out of bounds, and they knew that Fluffy (Hagrid’s three-headed dog) was guarding something there. For Snape to be sneaking around when all the other teachers were heading in a different direction was suspicious to say the least.

Their misgivings were reinforced when Harry went to get his confiscated book back from Snape and saw his nasty bite from Fluffy. That combination of factors, plus their intense dislike of their Potions teacher, made them believe he was up to no good. As a result, you could argue that without the troll they might not have started to suspect Snape. However, we don’t think that this would have been the case. We believe that they would have questioned his intentions anyway.

If Harry had still seen Snape’s injured leg, we think he still would have come to the same conclusion. If he hadn’t seen it, then we think they would have doubted him after the Quidditch match in which Harry’s broomstick seemed to have a life of its own – especially after they spotted Snape mouthing what we now know was a counter-curse but looked like an attempt on Harry’s life. After that, they misinterpreted the conversation between Quirrell and Snape in the Forbidden Forest as further evidence of Snape’s guilt. Even though they had the wrong end of the stick, there was more than one event that led them to doubt him. Overall, we believe their hatred for him, and his shifty behaviour, was enough to make them not trust Snape – with or without the troll in the dungeon.

Would Voldemort have got the Philosopher’s Stone?

If the troll had never been in Hogwarts, we think that Voldemort might have been able to come into possession of the Philosopher’s Stone – especially if the Harry, Ron and Hermione hadn’t become friends as a result of that night.

Once they went through the trapdoor, each of the trio had a significant role to play in rescuing the Stone. If it wasn’t for Harry’s flying skills, they might not have got past the keys. If Ron hadn’t been so great at wizard chess, they might have been stuck there. Finally, if Hermione hadn’t figured out the potions puzzle, and they had taken a drink from the incorrect bottle, they could have died. We highly doubt they would have undertaken such a dangerous adventure together if they weren’t firm friends.

Besides, they probably wouldn’t have got to that stage without Hermione as part of the team. While they all played a part in retrieving the Stone, it was Hermione who figured out the identity of Nicolas Flamel, and what was being hidden at Hogwarts in the first place. Without her brain, Ron and Harry would probably have been stuck.

If they were friends, without this specific incident, there is the slim possibility that they might not have realised that whatever Fluffy was guarding was under threat until it was too late. It wasn’t until they began to suspect Snape that they really started to put this together. Having said that, we are confident that Harry, Ron and Hermione would have managed to stop Quirrell and Voldemort in time – even if figuring out the initial mystery of what was being kept at Hogwarts took them a few extra weeks.

Most importantly… would Ron have ever mastered Wingardium Leviosa?

The Levitation Charm didn’t seem to come all that easily to Ron – he just couldn’t get the hang of Levi-o-sa vs Levi-o-SA. By the end of Flitwick’s lesson, all he had managed to do was get very cross at Hermione and be mean. Yet, when confronted by the troll later that day, he managed to use that spell to knock it unconscious with its own club.

Although, without finding himself in an extremely stressful situation, which required him to act on the spot, it could be argued that Ron would not have mastered Wingardium Leviosa. After his very frustrating lesson, he could have just tried to put it from his mind. His fury at Hermione might have made him too stubborn to correct his mistakes. Nevertheless, we think that he would have learnt it eventually.

Not only was it likely to come up again in some exam or class, but as a handy and basic spell Ron would definitely have had the capability to get to grips with it in the future. If he didn’t manage it on that Hallowe’en, with a bit of practice (and a change of pronunciation) he would have got there eventually.

Do you agree with our thoughts on this topic? What do you think would have happened if Quirrell had never brought a troll into Hogwarts?

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