Hundreds of dogs and their owners have descended on the Sydney Opera House for a concert specifically for canines.
Organisers say the event, the work of American musician and artist Laurie Anderson, is the first of its kind.
Ms Anderson called it "an inter-species social gathering on a scale never seen before in Australia".
It featured the cries of whales and high-pitched electronic sounds inaudible to human ears, accompanied by a bass guitar and violin.
For an hour or so Australia's most recognisable building became a giant kennel.
The sounds sent some agitated pets into a frenzy, while others seemed rather bemused.
"Most dogs are fine with it but we had to move away because he was getting a little bit freaked out by the whale noises," said one dog owner.
Ms Anderson said it was one of the best moments of her career.
"Supposedly, they are sort of like bats and whales that they can hear super high things and they can. Their hearing is so much better than ours.
"We didn't want to do something that humans couldn't hear too, so we chose a different bunch of things. A lot of dogs seem to enjoy classical music, frankly."
While the dogs' owners certainly enjoyed the show, we'll never know what their four-legged friends made of it.
These pets were a tough crowd. There were plenty of barks, howls and yawns along with the occasional snarl as the Sydney Opera House witnessed a piece of canine musical history.