Odd places to poke and stir. Behind there.. Your fingers might just reach. Dark places to get to, undusted and alive with spidery memories.

Let go. You don't need to address that. If people can't see it, why bother? If everything else you have on sight is new and shiny, who is going to worry about what lies there, at the very back?

It is not necessarily dirty, just hidden and inaccessible. Unless you remove all cover.

Those radiators are a pain; I shall never be able to wallpaper behind them.