If you were curious about how locks work and/or curious about what kind of person is a competitive lockpicker (as in they pick locks for sport) meet Schuyler Towne. He's completely obsessed with locks and loves to talk about 'em.
In his own words, he says the smell of brass and grease is invigorating to him. And he's 100% serious! I love the guy's passion, when you see him talk about competitive lockpicking, you'd believe it's a sport like any other. More informatively though, Towne describes how master keys work (something I was always curious about!) saying it's because of master wafers and shear lines. Right. Luckily, there's illustrations you can follow throughout the video.