Verschlossenen comes from the verb verschließen, meaning "to lock" or "to close". While the base verb is common, its use in this context makes it particularly intriguing.
In the song, the line "Hinter verschlossenen Türen" translates to "Behind locked doors". This phrase immediately suggests secrecy and intimacy, hinting at a private, perhaps forbidden, connection between the two people. It's a word that evokes curiosity about what happens when no one else is watching.
"Das wissen nur wir" is a duet about a spark two people feel the moment they meet, and everyone else notices before they're ready to admit it.
Beatrice Egli and Florian Silbereisen sing about the pull between them: people around them are already talking, already sure something's going on, while the two of them are still pretending it might not be. The chorus turns that tension into a promise: behind closed doors tonight, whatever happens is only theirs to know.
It's a warm, playful take on a secret that isn't really a secret at all, just a feeling neither of them can fully explain to anyone else.