Whodunit?When best friends Darcy and Norah have to create a fake business for a school assignment, they come up with a great idea: a detective agency! Darcy loves mysteries, and Norah likes helping people, so it's a perfect fit. But then their pretend agency gets a real case. Someone is missing, and it's up to Darcy and Norah to take on the search. Unfortunately, there's someone else out there who doesn't want the two detectives stirring up any trouble. . . .With the help of hidden clues, spy gadgets, and trusted friends, can Darcy and Norah crack the case in time?

WHO'S OUT THERE?Norah and Darcy's detective agency, Partners in Crime, is taking on new and chilling case. The girls' classmate, Maya, is hearing strange, crackling voices coming over the baby monitor while she's babysitting late at night. Maya is worried someone might be in danger. To help investigate, Norah and Darcy join her for a sleepover stakeout. In between eating snacks and watching TV, the girls are on high alert for anything suspicious. Soon, they stumble upon a mysterious secret they never could have imagined - but Norah and Darcy clash over how to interpret the new clues.Can the girls get past their differences to see their way to the truth?

Who's the culprit?Norah and Darcy are still in a fight, but crime doesn't stop just because the girls aren't speaking. Someone has set fire to their school's brand-new field house. And the prime suspect is Zane Munro, the cute boy Norah can't help crushing on. When Zane asks Partners in Crime for help, Norah and Darcy must band together to investigate. Norah knows Zane is innocent, but the clues are not in his favor. Can she and Darcy mend their friendship, crack the case, and clear Zane's name before it's too late?