There's a sense of magic in including a hidden room in your home, and there is, probably, none more magical way to do it than the bookshelf door. It's the sort of idea you imagine in old mansions with secrets to keep, but in reality, it's less of a gimmick than you think.
Using a hidden door is something that, beyond the fun of the design, is something that can be a solution to a problem — a (somewhat complex) way of simplifying the overall look, or avoiding everything feeling too crammed into a small space. Doors draw attention, and sometimes that's not where you want the eye to go.
