LANCE MACKEY HAD SOME BIG shoes to fill anyway. His father, Dick Mackey, won the Iditarod — the grueling, 1000-mile sled dog race — in 1978. His half-brother Rick Mackey would win in 1983. Lance had always wanted to win an Iditarod like his father, but in 2001, he was diagnosed with throat cancer.

He beat it. And then he came back and won the Iditarod. Four years in a row. Mackey’s story was made into a documentary which will be premiering next month. If you’re interested in learning more about the Iditarod, check out Brian Phillip’s 2013 article on the race — it might be the most beautiful piece of internet journalism of all time.