The Attack on HYDRA Research Facility Number 4 was the assault on the last known HYDRA base in Europe, coordinated by SSR agent Peggy Carter who led the Howling Commandos in the assault. It resulted in the capture of not just the facility but also the high ranking HYDRA official Werner Reinhardt and the seizure of numerous mysterious and deadly artifacts HYDRA had accumulated over the years.
Captain America and Strategic Scientific Reserve launched an attack on HYDRA Headquarters. As the Red Skull escaped in the Valkyrie, Rogers gained access to the plane and a fight ensued. Red Skull handled the Tesseract, which activated and sent him through a portal, while Captain America was forced to crash-land the plane in the Arctic, leading to his disappearance.
In a HYDRA Fortress in Austria, Werner Reinhardt tested the Obelisk's power on several of the Chinese villagers until he learned about Schmidt's demise on the Valkyrie and the approach of the Allies. Eventually he found a woman named Jiaying who was the only one able to hold the Obelisk without being harmed; however, with the Red Skull now dead and the Allies on the move, Reinhardt decided to move the Obelisk to a more secure location, locking Jiaying in a cage for later experimentation.
Two months later, the advance of the Allied forces into Austria forced Werner Reinhardt to order the evacuation of HYDRA Research Facility Number 4 and all of the numerous mysterious artifacts that HYDRA collected over the years. Reinhardt ordered a HYDRA Officer to carefully bring the Obelisk to him. The base was attacked by a group of Strategic Scientific Reserve troops led by Peggy Carter, Dum Dum Dugan, and Jim Morita. Reinhardt and his men were arrested, but Reinhardt warned Carter that if one of HYDRA's heads was cut off, two more would grow in its place. Carter promised to keep cutting them off.
Werner Reinhardt was given a life sentence in a Strategic Scientific Reserve prison called the Rat. In 1989, Undersecretary Alexander Pierce, one of the leaders of S.H.I.E.L.D. and secretly a HYDRA operative, granted him medical parole.
After being released, Reinhardt was taken back to his old base in Austria where he was presented with the elders of the Chinese village; among them was a young woman who had not only survived the Obelisk's effects but who also had not aged a day after forty-four years.
For a week, Reinhardt performed experiments on the woman which resulted in her death. Taking her bodily fluids and DNA, Reinhardt used them to get a transfusion that physically regressed himself back to his middle-age. With his youth restored, Reinhardt rejoined the ranks of HYDRA and by the next year, he had taken up the identity of Doctor Daniel Whitehall.