Dan and Amy Cahill are still determined to be the first to win the clue hunt started by their grandmother, Grace, who in her will, left the children either a million dollars or a clue. They are competing in this hunt against members of the four other branches of their family tree, who have fought against each other for hundreds of years, while at the same time producing some of the greatest minds in history. While Dan and Amy have sometimes "teamed up" with some of their relatives, they have often been betrayed. Their only consistent allies in the hunt have been their 20- year-old au pair, Nellie Gomez (who wears her hair in multiple colors and sports a snake nose ring), and their cat, Saladin. Each branch of the family holds claim to a specific strength (for instance, the Tomas branch excels at sports and exploration) and the characters take their basic attributes from these categories.

Though there are a large number of references to things that happened in earlier adventures (this is book 10), which have taken the children everywhere from Jamaica to Egypt, readers starting with this volume will still find Dan and Amy likable characters, and will get enough on-the- fly back-story to enjoy the adventure at hand, which begins in England. This time, the clue that shows up in the hotel where they are staying points to Shakespeare, and all the usual suspects are soon fighting it out on-stage at the Globe Theater.

A sense of sadness pervades the series, for Amy and Dan are orphans who, before the hunt even began, had been turned over to the uncaring Beatrice, who wants to send the two to foster homes. From the moment they began searching for clues, they faced danger, darkness and impending death -- but if they win the clue hunt, they might just find a sense of hope.

INTO THE GAUNTLET is a concept-driven book, heavy on the characterization, with a straightforward plot. This may be because THE 39 CLUES series is supposed to be an interactive experience, with prize money at stake (through December 31, 2010) on the Scholastic web site.