Shop The Adventures of Mary-Kate and Ashley Mystery Books
I Grew Up Reading Mary-Kate and Ashley's Detective Books and I'm Still Not Over Them
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Mysteries have always been my favorite book genre. As a kid who grew up watching Wishbone and Scooby-Doo and reading the entire Nancy Drew catalogue, I pretty much soaked up any mystery I could get my hands on. That includes all 10 of the Adventures of Mary-Kate and Ashley books. Based on the musical video series of the same name, the books are packed with '90s references and are like a trip back in time. Decked out in full trench coats, '40s detective hats, and matching sunglasses, Mary-Kate and Ashley Olsen grace the cover of each story ready to take on volcanoes, ghosts, UFOs, and, of course, space camp.
From eerie haunted houses to spooky cruise ships, there was nowhere these elementary-school-age sleuths would go that I wouldn't follow. Even as a third grader, I remember checking these out from the school library and holding onto them for as long as I could before I needed to return them. True fans will also know that, following the original 10 copies, the series continued on with almost 50 issues of The New Adventures of Mary-Kate and Ashley, which see a slightly older Mary-Kate and Ashley solving mysteries and maintaining busy social lives.
If you're familiar with Mary-Kate and Ashley's extensive list of films, I highly recommend giving these a quick read. Shop the action-packed books for yourself ahead, and hold onto your library cards, because the nostalgia is about to hit hard.
1 The Adventures of Mary-Kate and Ashley: The Case of the SeaWorld Adventure
What it's about: While playing in the woods one day, the girls come across a dead body that leads them and their parents — over-worked dolphin trainers at SeaWorld — to a mysterious cruise ship.
The Adventures of Mary-Kate and Ashley: The Case of the SeaWorld Adventure ($22)
2 The Adventures of Mary-Kate and Ashley: The Case of the Mystery Cruise
What it's about: The sequel to The Case of the SeaWorld Adventure, this book sees Mary-Kate and Ashley on the hunt for their father's missing laptop, which contains vital information that could help them solve the case.
The Adventures of Mary-Kate and Ashley: The Case of the Mystery Cruise ($14)
3 The Adventures of Mary-Kate and Ashley: The Case of the Fun House Mystery
What it's about: The girls are on a mission to find out what is making so many scary noises inside the fun house at their local amusement park. Their only clue so far? A pile of "monster mush."
The Adventures of Mary-Kate and Ashley: The Case of the Fun House Mystery ($9)
4 The Adventures of Mary-Kate and Ashley: The Case of the U. S. Space Camp Mission
What it's about: When a space shuttle is grounded due to a mysterious tapping sound coming from the outer surface, the girls enroll in a US Space Camp program to figure out what's wrong and help the shuttle lift off again.
The Adventures of Mary-Kate and Ashley: The Case of the U. S. Space Camp Mission ($21)
5 The Adventures of Mary-Kate and Ashley: The Case of the Christmas Caper
What it's about: Mary-Kate and Ashley aren't about to let Christmas be ruined when hackers break into Santa's computer to steal the "Spirit of Christmas," the plane he flies on Christmas Eve to deliver presents all over the world.
The Adventures of Mary-Kate and Ashley: The Case of the Christmas Caper ($7)
6 The Adventures of Mary-Kate and Ashley: The Case of the Shark Encounter
What it's about: When three pirates claim the sharks at a SeaWorld exhibit are singing, the girls have to figure out where the odd sounds are coming from.
The Adventures of Mary-Kate and Ashley: The Case of the Shark Encounter ($25)
7 The Adventures of Mary-Kate and Ashley: The Case of the Hotel Who-Done-It
What it's about: During a trip to Hawaii, the girls meet a hotel manager who needs their help solving a string of strange disappearances.
The Adventures of Mary-Kate and Ashley: The Case of the Hotel Who-Done-It ($6)
8 The Adventures of Mary-Kate and Ashley: The Case of the Volcano Mystery
What it's about: A snowball-throwing monster has been "terrorizing" a whole group of workers, so the girls set out to find out what's really causing the "snow" to fall.
The Adventures of Mary-Kate and Ashley: The Case of the Volcano Mystery ($29)
9 The Adventures of Mary-Kate and Ashley: The Case of the U.S. Navy Adventure
What it's about: UFOs have been seen flying overhead, so the girls team up with the United States Navy to solve the mystery of what's really orbiting above their hometown.
The Adventures of Mary-Kate and Ashley: The Case of the U.S. Navy Adventure ($27)
10 The Adventures of Mary-Kate and Ashley: The Case of Thorn Mansion
What it's about: When a ghost is rumored to be haunting a mansion in Transylvania, the girls set out to see who, or what, is behind the haunting.
The Adventures of Mary-Kate and Ashley: The Case of Thorn Mansion ($5)
