So you're two thirds of the way through a book/movie/whatever, when suddenly, the main protagonist dies, is imprisoned, performs a Face Heel Turn, or is otherwise unable to act as the main protagonist. All seems lost, a Take Up My Sword hasn't been pulled! What is to be done? In so far as it applies to sidekicks, it's a relative to You Are in Command Now, which applies to more rigid situations where the Big Hat Of Command lands on a person's head whether they want it to or not, based on their level in the hierarchy. Due to the nature of this trope, spoilers are bound to follow.