It isn't only every other person in your office who's walking around singing "Shine bright like a diamond," it's real musicians, too. Case(s) in point: The Jonas Brothers and Sia. Above, check out the JoBros delivering a sultry version of the Rihanna No.1. Yes, we just told you watch a Jonas Brothers cover of a Rihanna song! We swear it's good.

Below, Sia, the girl who actually co-wrote "Diamonds" (#themoreyouknow), completely SLAYS it to the point where we kind of wish she kept the song for herself. Only kind of. Check it out.