Ezra's Nanna is visiting and keeps interrupting his detective work which upsets him. She unexpectedly gives the Inbestigators a case to crack, which does give something for Ezra to be thankful for.
When the 'Treat Day' lunch orders are replaced with healthy foods Ezra goes off the handle and demands that he and the rest of the InBESTigators track down the reason for the substitute.
When Ezra is nominated for the Young Small Business Awards he seems far from excited and more like very upset as the time for the event grows near. Maudie enlists the rest of the InBESTigators to find the reason why.
Mr McGillick's cell phone seems to be missing at the Grade Five camp, Kyle stands accused of taking it as one of his pranks. It's up to the InBESTigators to look up the real thief.
When a birthday party that Ava throws for a lovesick teacher has an ice cream birthday cake vanish during the party, the InVESTigators come to catch the thief cold.
At a school fundraiser, a lemonade stand is doing very well until it is sabotaged. Amelia's accused of this sour deed because her cupcake stand is doing poorly. In steps the InBESTigators to aide in finding real villain.