Z-dark search with the ATLAS detector

The search of the “hidden sector” via new neutral light bosons Z-dark ($Z_d$) could be revealed by the study of the decay of the discovered Higgs-like boson or any other undiscovered Higgs boson. After the LHC concluded a successful first period of running, the ATLAS Collaboration published its latest results on the $H\to Z_d{Z}_d\to 4l$ analysis using up to 20 fb${}^{-1}$ of integrated luminosity at $\sqrt{s}=8$ TeV. In this proceeding I present a summary of the recent results on the search of the $Z_d$ in the signature $H\to Z_d{Z}_d\to 4l$ with the ATLAS detector at the LHC.