Early in the Cold War era, Daniel Whitehall was one of the foremost spymasters in the world, presumably coming from a background in British intelligence. He was a master manipulator and prided himself on making people become who he believed they were meant to be. Somehow, he had access to technology far advanced for the time and used it to create a suit of armor. Along with serving as a sophisticated weapons system, the armor disguised his true identity and allowed him to be known as the Kraken to most.
Kraken was created by Jonathan Hickman and Stefano Caselli as one of the many characters in the Secret Warriors ongoing series. The character was retconned into being one of the prominent leaders and architects of HYDRA.
One of the surprise twists of the Secret Warriors series was that Kraken had actually died before the events of the book and was being impersonated the entire time by Jake Fury. The true Kraken appeared only in flashbacks.
Major Story Arcs
Wheels Within Wheels
Along with several other prominent leaders in the intelligence community, Daniel Whitehall was invited by Leonardo Da Vinci to join the Great Wheel in 1961. The arrangement was a simple one. In return for cooperating on a few select missions for Da Vinci, he would give all of them the means to win their own secret wars. To protect their anonymity, each member was given a codename based on the Zodiac. Whitehall was codenamed Leo.
Each of the Great Wheel's missions involved the acquisition of strange technology. Whitehall teamed with Vasili Dassiev, Shoji Soma and John Garrett to salvage the power source from a crashed Brood vessel in Egypt. It was there that he revealed his Kraken power armor in order to fight off a swarm of Brood drones.
Ultimately, the Great Wheel was betrayed by Dassiev and Viktor Uvarov for the acquired technology. Their alliance would become the organization known as Leviathan. They attempted to have the rest of the Great Wheel killed, but Whitehall used his Kraken armor to protect himself and fled with Baron Strucker and Shoji Soma. Their alliance would become HYDRA.
Wake the Beast
Now more Kraken than Daniel Whitehall, he was a key figure in the creation of HYDRA along with Baron Strucker. But unlike Strucker, he orchestrated things from the shadows and chose not to make himself widely known. He continued to turn people into who he believed they should be, which led to him practically creating the rest of the leadership of HYDRA.
Kraken ran an orphanage of nearly a hundred orphaned girls, forcing them through training and tests until he was left with just one. That girl became Viper. He conducted the experiments that led to the creation of the Hive. He discovered the Gorgon at a young age and presented the murderous boy with the Godkiller sword. Then after creating all this in the name of HYDRA, he found out he was dying.
Kraken met with his old friend Strucker one last time and shared the news of his fatal illness. He feared he would not live to see the completion of their plans, namely the deaths of Nick Fury and Viktor Uvarov.
Three years later, Whitehall lied dying in a hospital better, where he was found by Jake Fury. Jake had already been to Whitehall's London home, where he found the journals Whitehall recorded everything in as well as the Kraken armor. With all that, Jake made it known that he intended to impersonate Whitehall as Kraken. He donned the armor and cut off Whitehall's life support, killing the true Kraken.
Daniel Whitehall appears as the main villain of Season 2, portrayed by Reed Diamond. Flashbacks reveal that during World War 2, Whitehall was originally a German HYDRA operative by the name of Werner Reinhardt, who worked under the Red Skull. Reinhardt began experimenting on a Kree Obelisk that had been left behind on Earth thousands of years ago, believing the object held the key to life and death itself. Before he could make much headway, the Red Skull was killed by Captain America during the events of The First Avenger, and Reinhardt was subsequently taken into custody by Peggy Carter and the Howling Commandos. Reinhardt spent the next four decades rotting in prison, before finally being pardoned by Alexander Pierce (in reality a high-ranking HYDRA operative that had infiltrated S.H.I.E.L.D.) in the 1980's.
Upon his release, Reinhardt resumed his research in secret, eventually finding a young Chinese woman who had taken prisoner during WW2, who had not only survived touching the Obelisk (which apparently kills any human who touches it), but had miraculously not aged whatsoever since the 40's. Reasoning that the woman somehow contained the secret to eternal youth, Reinhardt murdered and dissected her, eventually using her body to rejuvenate his own frail form. Now going by the Americanized moniker of Daniel Whitehall, he once again sought to unlock the secrets of the Obelisk.
Decades later, Whitehall's HYDRA cell was brought to the forefront following the events of Captain America: The Winter Soldier, where HYDRA's infiltration of S.H.I.E.L.D. was exposed and stopped by Captain America and his allies. He eventually partners with the unnamed father of Skye (the daughter of the Chinese woman he murdered) to decipher the secrets of the Obelisk, which is revealed to be called the Diviner.