HYDRA was the research division of the Nazi Army, led by Johann Schmiddt; also known as the Red Skull. It was also the advanced science branch for the Third Reich. The organization went rogue from the German forces later and was armed with heavily advanced technology created by Arnim Zola using the power of the mythical Tesseract. HYDRA agents used cyanide pills to kill themselves to avoid interrogation after being captured. The orginization was belived no existant after the events of The First Avenger but it was revealed Hydra still existed in The Winter Soldier. Hydra is now one of the main villans in the Agents of S.H.I.E.L.D. tv series.