Deepfake videos on TikTok can be fun. They can also be malicious.

Facebook, Twitter, YouTube and TikTok have banned deepfakes, which are realistic but fabricated or manipulated representations, often of public figures. Yet a TikTok video in which a fake Tom Cruise serenades the real Paris Hilton went viral. That video is one of dozens from the account @DeepTomCruise. The account has racked up almost 4 million followers with its digital simulations of the famous actor singing, golfing and, of course, laughing in a slightly too intense way. Marketplace’s Meghan McCarty Carino speaks with Anjana Susarla, professor of responsible artificial intelligence at Michigan State University’s Broad College of Business. She said we can thank TikTok’s algorithm for keeping deepfakes alive.