There were two cats in two burning houses. Joker made him choose. (pic via WCHS TV)
John Buckland and Troy Marcum are two West Virginia guys who dress up as superheroes sometimes, but not to be weird. They do it as part of Buckland's Heroes 4 Hire service, attending children's events and teaching kids positive stuff, like how to bravely battle the flames of a burning house to save a fellow creature of the night, the common housecat.
Buckland (Batman) and Marcum (Captain America) were on their way back from an event at the local American Legion Post when they spotted a house on fire. Since Buckland is a former firefighter and Iraq war vet, he's arguably ten times braver and more skilled in an emergency than your average Dark Knight. So he sprang into action and burst into the house with Marcum to make sure no one was inside.
For the remainder of this story I'll just refer to them by their superhero identities.
According to Batman, the house was too dense with smoke for the Dark Knight to make any headway, so in a rare alliance between the DC and Marvel universes, Captain America came to Batman's aid by knocking out one of the windows to clear some of the smoke. Thanks to Captain America's heroism, Batman was able to inspect the house for any living creatures, human or otherwise. It was then that Batman found the home's resident housecat, left behind by its owners who were away on a trip.