Brave, clever and never more than a whisker away from adventure! When the museum’s visitors are gone for the day, it’s time for the cats to come out to play. The kittens are exploring The Silver Lion, an old galleon that Boris is sure was once a pirate ship, when the rats appear with a treasure map. Intrigued, Boris hatches a plan to follow the rats, but after chasing them all over the museum there is still no sign of the treasure. The kittens are mystified. What are the rats up to?