The structure of a thiolate-protected Au cluster, [Au-44(SR)(28)], is theoretically predicted via density functional theory calculations. Au-44(SR)(28) is predicted to contain a "two-shell" face-centered-cubic_type of Au kernel and possess chirality. The predicted cluster structure is validated by comparison of optical absorption properties between theory and previous experiments, as well as energy evaluations. Based on the predicted cluster structure, the magic stability of Au-44(SR)(28) is understood from the superatom electronic configuration and formation of a unique double-helix superatom network inside.