"In the age-old battle between cats and dogs, one crazed feline has taken things a paw too far. Kitty Galore, formerly an agent for cat spy organization MEOWS, has gone rogue and hatched a diabolical plan to not only bring her canine enemies to heel, but take down her former kitty comrades and make the world her scratching post. Faced with this unprecedented threat, cats and dogs will be forced to join forces for the first time in history in an unlikely alliance to save themselves -- and their humans."
(Above taken from here).
A pretty good movie, with some funny parts. If you liked the first one, you'll like this one. If you didn't see either yet... Well, you should watch them at least once.
And, before anyone asks, Kero slept through the movie, so I'm not sure if he didn't enjoy it, or was too tired, or - being asleep when it started - didn't even notice there was a movie with dogs in it on TV.