The London Eye Mystery, by Siobhan Dowd

What goes up must come down. However, in The London Eye Mystery, by Siobhan Dowd, when Ted's cousin, Salim, goes up in the London Eye, a monstrous farris wheel of sorts, he doesn't come back down. Since Salim  and his mother, Ted's Aunt Glo, were only visiting for a couple of days before moving from London to New York, Ted and his sister, Kat, feel extremely responsible for the dissapearance of Salim since they were the ones that let him go on the thirty minute spin alone in the first place.

Ted's natural tendency is to pay attention to the most minor of details, which comes in handy as the two pour over photos taken from the day, visit the scene of the disappearance, unravel word puzzles and track down potential suspects; filling in the blanks where the police came up short. The characters that surround this mystery are what really make it a great ride: Aunt Glo with her smoking and high strung tendencies, Kat with her effortless beauty and understanding, and Ted with his quirky obsessiveness and gradual acceptance of who he is.