If you live in or around Philadelphia, you’ve probably heard unexplained booms well into the night. They started during the protests against police brutality, which has the city chalking them up to fireworks and ATM robberies, while some concerned citizens are looking to conspiracy theories. Max Marin and Michaela Winberg, reporters for WHYY’s Billy Penn, investigated the #PhillyExplosions and some inconveniently-timed changes to Philadelphia’s fire code.