Howard Mitchell was the former owner of Mitchell Armored Truck Company and later became known as Hijacker during his voyage in Peru. He was recruited by HYDRA under the leadership of Olinka Barankova and became an honory member of the Cabal.
Living in the United States of America, Howard Mitchell was known as the owner of an armored truck company, but was unsatisfied with his personal profits. He decided then to steal his own trucks. To do so, he created a customed identity, including own-developed technology, and became the "Hijacker". As the Hijacker was familiar with all of the secrets of Mitchell's company, he managed to perform four successful thefts. He never killed a witness, because witnesses could not identify him due to his armor and disguise.
Recruited into HYDRA
Ever since he continued to cause more thefts since the battle of New York, this drew the attention of HYDRA and was recruited by Olinka Barankova, who made gave him a seat in her own team called the Cabal.
Hijacking Stark Industries
Following the Infinity War, Howard, along with Frank Smith, Liso Trago, and Ramond Theis, led a gang of HYDRA thugs were successful in hijacking a Stark Industries truck filled with Iron Man armor. Their job was to take the truck back to their employer. That was when they meet the Ant-Man and Wasp. Trying to avoid them on a freeway, Howard and his thugs were easily overwhelmed and beaten by the couple. Mitchell was taken into custody by the FBI and sent to prison.