Stranger Things became a sci-fi phenomenon when it debuted on Netflix in 2016. Fans immediately fell in love with the series’ nerdy pre-teen protagonists, Mike, Lucas, and Dustin and their friendship with telekinesis-powered Eleven. Together, they went on a mission to save their friend, Will, from a terrifyingly creepy alternate dimension known as the Upside Down (and to save Barb, but more on that later).

Between Mike’s nobility, Lucas’ instincts, Dustin’s adorable grin, and Eleven’s fierce and naive nature, it wasn’t hard for the show to become a fan favorite. But as with any TV craze, the show’s popularity goes beyond what fans already know, and has sparked a number of conspiracy theories about the characters, the setting, and the plot of the show.

Like other sci-fi series, the show inspires fans to create theories and speculate on what’s to come next for the series’ next season. As mentioned earlier, Barb was the first victim (that we know of) to be taken into the Upside Down in Hawkins. While Mike’s sister, Nancy, saw her decomposing body in the wasteland, fans are still holding out hope that Barb is still alive—even if she’s become the villain.

Just like Will’s mom, Joyce, who was one of the few adults to believe in the impossible (which led to the epic scene with Christmas lights), we’re all for delving into conspiracy theories. If you want to dig into your suspicious side, grab your tin hat and get set. Here are the best Stranger Things conspiracy theories. They may sound far-fetched, stranger things have happened.