by Nina Alexander, 61 pages . Mary-Kate and Ashley are so excited to be away at summer camp! Some kids tell them the camp is haunted, but Mary-Kate and Ashley don't believe it. But then things start to get a little weird. First th...

by Judy Katschke, 61 pages . Trenchcoat Twins Case Report ... From Mary-Kate and Ashley How scary is this: it was Halloween, and Ashley and I didn't have a mystery to solve! Yikes! But things were about to get even scarier.

by Melinda Metz, 61 pages . It was like a fairy tale come true: Ashley and I got invited to a royal ball in honor of a real live princess! We couldn't wait to meet Princess Glorianna. But right before the ball, the princess w...

by Judy Katschke, 57 pages . Talk about style! Ashley and I were invited to a cool costume party at the house of a famous mystery writer, Fiona O'Leary. We couldn't wait to hit the ballroom for the big 1920's dance contest. Th...

by Alice Leonhardt, 63 pages . Ashley and I set sail on a fantastic cruise vacation - our whole family. The Ocean Queen had everything - pools, water slides, a video game arcade, even a Super Scavenger Hunt for the kids! But thi...

by Pauline Preiss, 63 pages . Do you believe in dragons? Ashley and I didn't - until we went to the Logical I dude ranch. Strange noises in the middle of the night ... a terrible smell coming from the well ... things at the Logica...

by Judy Katschke, 61 pages . Mary-Kate and Ashley are looking forward to spending quality time with their Bassett hound, Clue - at a special sleepaway camp for dogs and their owners. But as soon as the three of them arrive at Cam...

by Carol Ellis, 63 pages . Ashley and I were planning an awesome Halloween party with our friends. But everything started going wrong. Spiders in the pinata ... scary warnings ... damaged decorations ... we thought it was all s...

by Mary-Kate Olsen, 55 pages . The "Jingle Bells on Ice" skating show was just a few days away - and the skaters needed our help! The lights went out during rehearsal, skates disappeared, and the ice turned to slush! Was the Jingle...

by Carol Thompson, 53 pages . Mary-Kate and Ashley are at Sea World with their parents, who are hard at work creating a computer program that will let humans speak with dolphins. The twins can't seem to find a mystery - until they...

by Nancy E. Krulik, 63 pages . Madam Zelda, Ferris Wheel Fred, and Carousel Cal are desperate for help. They need Mary-Kate and Ashley, also known as the Trenchcoat Twins, to get rid of that monster in the amusement park! For ag...

by Laura O'Neil, 63 pages . While touring Hawaii, Mary-Kate and Ashley realize that a clever thief is on the loose at their fancy hotel, stealing gold, silver, and jewels from fellow guests. But the Trenchcoat Twins are determin...

by Carol Thompson, 51 pages . Three mushroom-mining prospectors have been scared away from their mine by a claim-jumping, snowball-throwing monster. In a wild volcanic wilderness like Jelly Jungle, what kind of monster can the twi...

by Nina Alexander, 63 pages . Spooky Thorn Mansion is deserted - and full of mysteries for Mary-Kate and Ashley to solve. There's an eerie humming noise, puddles of mysterious goo on the floor, and a strange thick fog emitting fro...

by Lisa Banim, 95 pages . Dear Diary, Today was the worst day of my life. I tried out for the White Oak softball team, and it was a total disaster. I couldn't do anything right. I never even made it to the first base. I mis...

by Judy Katschke, 89 pages . To Kiss or Not to Kiss ... Mary-Kate has a great new hobby - acting! She's got the star role in the next school play. And she's thrilled to find out that her leading man will be Ross Lambert - a su...

by Megan Stine, 85 pages . The annual Spring Fling's coming up and Mary-Kate and Ashley have hot dates for the dance. At least they think they do - until they find out their dates have asked other girls instead. To make matters...

by Judy Katschke, 95 pages . Dear Diary, I'm on a beach in Florida - and I'm in trouble! When Ashley and I got here for our school trip, I thought everything would be great. What could be better than sun, sand, and cool guys w...

by Nancy Butcher, 95 pages . Dear Diary, So far this school trip to sunny Florida has been a blast. I've even been made captain of our triathalon sports team! But now Dana Woletsky has shown up and she wants to take the team a...

by Megan Stine, 95 pages . The heat is on! The good news is - Mary-Kate made the White Oak winter sports team! The bad news is - she has no money to buy her own snowboard. She asks Ashley to help her, but Ashley has p...

by Judy Katschke, 91 pages . Mary-Kate and Ashley can't wait to go home for winter break. But they wind up stuck in a Harrington dorm instead. To make matters worse, the headmaster thinks that doing endless chores is more fun tha...