I thought Lake Monster Mix-Up was a pretty good mystery story. It sort of reminded me of Scooby-Doo, both in terms of its innocuousness, and in terms of its premise (a couple of kids attempt to solve mysteries with their doggie detective companion). The mystery was suspenseful and slightly hair-raising, but I really don't think it would be terrifying to too many kids. It sort of rests between stories in which a doll has gone missing, and stories in the vein of the Goosebumps series. The graphic novel format was a great way to tell the mystery because good visualization skills are often needed in order to unravel a mystery story. If a reader needs visual aids in order to support that process, then a graphic novel is the way to go.My niece likes the idea of mystery stories, and she likes the idea of graphic novels, so I checked this out for her. I think she would have enjoyed the story, I think she would have found the vocabulary to be right at a comfortable reading level for her, and I think she'd have wanted more stories from this series. Unfortunately, she barely even looked at this book, and I'm not really sure why. The illustrations are all black and white, no color, so maybe she just likes her graphic novels to have some color (can't say I blame her). It's also possible that she is just approaching the age where she needs and wants to choose her own books. If so, yea (but WAH!!! My girl is growing up!)! :-)