The progress of metaoptics relies on identifying photonic materials and geometries,the combination of which represents a promising approach to complex and desired optical functionalities.Material candidate options are primarily limited by natural availability.Thus,the search for meta-atom geometries,by either forward or inverse means,plays a pivotal role in achieving more sophisticated phenomena.Past efforts mainly focused on building thegeometric library of individual meta-atoms and synthesizing various ones into a design.However,those effortsneglected the powerfulness of perturbative metaoptics due to the perception that perturbations are usually regardedas adverse and in need of being suppressed.Here,we report a perturbation-induced countersurveillance strategyusing compound nanosieves mediated by structural and thermal perturbations.Private information can be almostperfectly concealed and camouflaged by the induced thermal-spectral drifts,enabling information storage andexchange in a covert way.This perturbative metaoptics can self-indicate whether the hidden information has beenattacked during delivery.Our results establish a perturbative paradigm of securing a safer world of information andinteet of things.