When Sarah wants to feed the family rabbit, she found horrified: Fridolin has gone! Has she really forgotten to close the barn door? Although Sarah is suspicious footprints, nobody wants to listen to her. Only Justin and Anna believe her. Together they decide to go to the thing on the ground. In their investigation, the three animal agents encounter a sinister plot and a dark secret! Take on the role of Anna, who spends on the farm of her uncle for the summer, or as Justin fathom the mystery of the stolen animals.