IT: Welcome to Derry is turning heads with how it handles the Stephen King universe, the secrets hidden in Derry, and the horror of the monster. Apart from its dedication towards delivering on the absolutely chilling aspects of the monster's attacks in Derry, the HBO Max show has also managed to hide one of the biggest references to King's larger universe quite plainly. This reference is never actively pointed out and is only visible to the real connoisseurs of the Stephen King multiverse.Keep reading to find out what reference is hidden in the IT: Welcome to Derry series and what it could mean for the larger multiverse, that is, the Stephen King world.IT: Welcome to Derry hides a wild Stephen King reference in plain sightWhen it comes to shared universes, or multiverses as we call them, Marvel, DCU, and Star Wars come to mind. However, there was an iconic multiverse that existed even before any of these multiverses were established. The Stephen King multiverse has spanned almost all of his books, starting with the 1978 The Dark Tower series. A majority of Stephen King's stories find their history and references dating back to the 1978 novel.Such is the case for the IT novel series created by Stephen King. In The Dark Tower series and King's multiverse as a whole, Maturin the Turtle is the most common form of the cosmic deity who created the universe. As the Stephen King legend goes, Maturin the Turtle emerged from his shell and vomited the cosmos. Maturin's vomiting of the cosmos is considered the starting point for the universe's existence.In the IT series, Maturin the Turtle's vomiting the cosmos into existence is also the starting point of the monster released from the Void. Therefore, Maturin the Turtle's creation of the cosmos connects the IT series to King's shared multiverse. However, ahead of IT: Welcome to Derry, the connections these stories share with the rest of the Stephen King references were mainly erased, and the narratives were treated as stand-alones.This is where IT: Welcome to Derry finds itself different from the people surrounding it. Andy and Barbara Muschetti's HBO Max original has wholeheartedly adopted the Stephen King universe, be it The Shawshank Redemption or The Shining. While these references were fairly obvious, there's one wild detail that was well hidden.IT's Pennywise (Image via HBO Max)The hidden detail is the multiple appearances of a turtle.The first time we spot a turtle on It: Welcome to Derry, it is seen as the Derry High School mascot, warning its students about nuclear safety. The next time Lily and Matty exchange their charms, Lily receives Matty's purple charm. The continuous appearance of a turtle appears to be a major Stephen King reference pointing towards Maturin the Turtle.Throughout the Stephen King multiverse, Maturian appears to be a benevolent creator looking to help its subjects in various situations. So, the presence of the Maturian Turtle throughout It: Welcome to Derry might be referring to the later entry of an overarching protagonist who can save the town of Derry and its people from the monster's horror.Only time will tell if the references point towards some real action on IT: Welcome to Derry, or if it is just that, a reference to evoke reminiscing in the viewers.Keep following Soap Central for more such interesting insights into your favorite shows!