Cameo is an app that connects celebrities with fans for a very specific purpose: Fans can pay for the celebrity to film a personalized video for them—wishing them a happy birthday, for example. Growth was steady, but then potential disaster struck: A group of white supremacists tricked one of Cameo's most famous celebrities into filming a video with coded hate speech. Cameo knew it needed to fix this problem quickly, before other celebrities started to distrust the platform. Here's how Cameo sprung into action.