The stunt took weeks of preparation. Building a tank. Training with freedivers and magicians. Developing the filming schedule. The end result of the effort, a new episode of YouTube star Michelle Khare’s series Challenge Accepted in which she attempted to recreate Harry Houdini’s deadliest trick, has since garnered more than 4.5 million views on YouTube. The final product has a production quality that would rival what’s on “traditional” TV (in fact, magician David Blaine attempted a similar stun...