There is nothing the Super-Pets love more than spending time with their heroes, but they're finding it difficult to be taken seriously as members of the team when their humans just don't understand them. But when Mr. Mxyzptlk (a magical imp from the fifth dimension) arrives in Metropolis with a plan to wreak a little chaos and destruction, the Justice League is caught in his trap! The Super-Pets will need to come up with a plan to prevent Myx's mischief from destroying the city-while somehow trying to rescue their human counterparts. The only problem is, they may need to recruit their greatest enemy in order to defeat him. DC League of Super-Pets: The Great Mxy-Up picks up immediately from where the movie leaves off!.