It can make for some neat video party tricks … deepfakes that swap someone’s face for another or put characters in scenarios way out of context. This clip of Bill Hader morphing into Tom Cruise as he does a vocal impression went viral this year.

When BuzzFeed and Jordan Peele made a similar video earlier last year, using Peele’s uncanny Barack Obama impression, the warning was even more clear: This technology could be used to create more fake news and erode trust in what we believe because we think we see it.

To teach us more about how deepfakes work and how they could be weaponized, we turned to Hany Farid. He’s a professor at Berkeley’s School of Information and the Department of Electrical Engineering & Computer Sciences.

Plus, professional dogsledder and writer Blair Braverman answers the Make Me Smart question.