"*Shadows"@en . . . . . . . . . . . . . . . . "HYDRA Research Facility Number 4"@en . . . . "The HYDRA Research Facility Number 4 was one of HYDRA's facilities in Austria during World War II. It was used to contain many mysterious artifacts discovered by HYDRA's researchers."@en . "Agents of S.H.I.E.L.D."@en . "The HYDRA Research Facility Number 4 was one of HYDRA's facilities in Austria during World War II. It was used to contain many mysterious artifacts discovered by HYDRA's researchers."@en . . . . . . . . . . "HYDRA soldiers"@en . .