From the constant reminder that any actor can be written off without warning to the extreme secrecy that forces cast members to hide major plot twists—even from each other—the video breaks down the behind-the-scenes rules that keep Blue Bloods running like a disciplined NYPD unit. But just as the cast explains how tightly they must stick to the script, maintain their characters’ exact looks, and show up to set in a flawless “family” mood regardless of real-life stress, the most surprising rule of all emerges—so let’s watch the video to see what the cast must face next…