It all started with one mysterious briefcase.... When Allie's father dies, her half sister, Kat, is left in charge of his detective agency -- and of Allie. Despite the many changes in her life, Allie can't help being excited by the possibility of being close to some real private-eye adventures, the kind she is always daydreaming about. So when a man comes to the agency asking Kat to guard his briefcase, it looks like Allie will get her chance to investigate. But when Allie breaks into the briefcase, she makes a shocking discovery. And when she begins asking around, she realizes she may have taken on more than she bargained for. Whoever wants the briefcase kept safe desperately needs the agency's help, and whoever wants them uncovered will do anything to find them.... Grade 5-7-Allie, 12, longs to work on cases with her 28-year-old half sister, Kat, who runs their recently deceased dad's detective agency. When a mysterious man employs the private investigator to hold his briefcase for him, Allie is suspicious, and when he becomes a hit-and-run victim, she tries to convince her sibling that something is fishy. The fledgling sleuth secretly opens the briefcase and finds five issues of Gypsy Witch. With friend Mei in tow, she questions the proprietor of Comics Galore, who tells her that the comic books are rare and she deduces that they are worth a fortune. The rest of the case unfolds as the sisters pursue clues, learn that the hit-and-run was no accident, and find themselves in peril. This fairly fast-paced mystery has trendy writing and lots of dialogue and will entertain readers not yet ready for Wendelin Van Draanen's "Sammy Keyes" novels (Knopf). Karen Hoth, Marathon Middle/High School, FL Copyright 2003 Reed Business Information, Inc. Gr. 5-7. Sixth-grader Allie lives in the shadow of her brilliant half-sister, Kat, who inherited their father's detective agency when he died. Business is slow until a mysterious man with a briefcase appears. After the man ends up unconscious following a hit-and-run, Allie smells a larger criminal conspiracy, so she breaks her sister's confidence (and the law) by picking open the mysterious briefcase and discovering five Gypsy Witch comic books--worth an estimated million dollars, and even more than that to the senile old man who claims to have lost them. It's a classic good-PI, bad-PI comic duo, with Kat following procedure and Allie never missing a chance for comic mischief. But when Kat sets a trap to catch the thief, things get serious--and Allie has to break the rules again to try and save her sister. Although there are some hackneyed motifs that intrude on the action and the dialogue is excessively explicative, readers will be carried on by concern for the characters and the exciting, but never terrifying, twists and turns. John Green Copyright © American Library Association. All rights reserved A Virginia author of more than twenty-four novels for children and teens, Alison Hart is an avid horse rider who loves a good mystery.