Tweety Bird and Sylvester get another run at the big screen. All images courtesy of Warner Bros. Animation.

After tackling Road Runner and Coyote in CG and 3-D last year, producers Sam Register, Tony Cervone and Spike Brandt along with director Matt O'Callaghan turned to another pair of Looney rivals, Tweety Bird and Sylvester the Cat in I Tawt I Taw a Puddy Tat. Only this time, they had a secret weapon up their sleeve: a CD of the eponymous 1950 novelty song sung by the late Mel Blanc and performed by the Billy May Orchestra. So, armed with the song, O'Callaghan and the team (including Reel FX, which once again did the animation and stereoscopic rendering) went about animating to the signature Blanc vocals and jazzy beat. Boy, does it swing, as Sylvester chases Tweety and Tweety clobbers Sylvester inside and outside a New York apartment while Granny tries to sleep. And the 3-D has both great horizontal and vertical depth going for it as well.

"I was just wrapping up the three Coyote shorts and Sam walked into my office and handed me this CD with some of these songs on it and said they had never been animated to," O'Callaghan recalls. "And that it would be really fun to put the classic Mel together with modern technology in a short. The problem was the content and so he handed it to me and I had to put together a pitch.

O'Callaghan had to time the action to the eponymous 1950 novelty song.

"And I think when I first listened to the song, I realized that it's a very sweet duet, which would be painfully boring if we just animated to that. But then getting more familiar with these shorts, watching them over and over again, there was such a great dynamic between cat chases bird and my first approach was to tonally make it feel like the old shorts. The only way I could it was to fit the punctuation of all the gags in between the lyrics, and so I pitched that idea with some boards, humming the song. And everybody laughed and I said this is what that has to be: a combination of very sweet song and very physical gags."

And the funny counterpoint wonderfully captures the spirit of the old rivalry. But because they were tied to the song, they had a newfound discipline that they didn't have to worry about in the previous Coyote shorts.

"So I had to position the right gag at the right place and there were some great gags that just didn't fit," he continues. "So I had to be very calculating and had to be very honest with stuff that didn't work. So then when we threw it in a New York apartment, that had great depth of field like the Coyote shorts, and that helped it swing a certain way. So I said, 'Well, if I'm going to be in a New York apartment, I'm going to go outside because that's going to give me full advantage here.'"

Sometimes, in fact, O'Callaghan had to work backwards in keeping with the punctuation of the gag and to figure out how to arrive at the right moment in the song. "It was ridiculously challenging but a ton of fun," he admits.