Are there any guns that are actually silent (or nearly so) as the movies would have it?

My interest is that I want to buy a bb gun or air rifle to kill chipmunks at close range, but I’d like to get one quiet enough that the neighbors don’t freak out. I’ve checked, and it’s legal for me to own and shoot an airgun at chipmunks in my backyard. But a firearm would be illegal, and I don’t want any misunderstandings.