Abstract: Ultrathin plasmene nanosheets are demonstrated as a new class of flexible surface enhanced Raman scattering (SERS) substrate capable of conformal attachment and sensitive and reproducible detection of chemicals on topologically complex surfaces. Engineering building block morphologies allows for fine-tuning of the SERS performance. In a preferred application the plasmene nanosheets are demonstrated as the next generation plasmonic and/or SERS coded labels, such as for example, anti-counterfeit security label for banknotes. Engineering the morphologies of plasmene-constituent nanoparticles and varying of SERS molecular labels offer virtually unlimited coding capacities.