THE CATT had discovered a real, (still somewhat) live, MOUSE! As I came in the house, I caught him in the act of trying to stuff it in my shoe... after he fiddles and bats at it for a while, he hears Tjhien coming to the door, and fearing it may be nabbed, he grabs it in his jaws and leaps through the CATT FLAPP presumably to continue enjoying it in private.