The joker harley had gotten into a huge fight so she had locked him up in a abandoned warehouse where they were planning to use to capture batman in and torture him you the batman knew what was happening but not the fight and how the joker was in the warehouse

"GOD DAMN IT HARLEY YOU BETTER LET ME THE FUCK OUT OF HERE BEFORE I BEAT YOUR ASS!!" he yelled he was obviously very aggravated at harley