(Captain America: Baron Strucker. HYDRA's number one thug.) Technically, I'm a thug for S.H.I.E.L.D. (Captain America: Well then technically you're unemployed.)
~ Captain America and Wolfgang von Strucker.
Like all of HYDRA's leaders, Strucker had little to no morality at all. He was perfectly fine with performing experiments on human beings, not worrying about how many of them would die, as he believed that the results gathered from the experiments would contribute to HYDRA's cause. He was also unconcerned about the civilian casualties in the nearby city of Novi Grad during the Attack on the HYDRA Research Base.
According to another HYDRA head Gideon Malick, Strucker understood that protecting assets was more important than flaunting them, as he would never foolishly put an untested young operative in play without proper training.
Captain America: The Winter Soldier
Wolfgang von Strucker only appears in the mid-credits scene of the film. He is revealed to be one of the leaders of HYDRA after it infiltrated S.H.I.E.L.D. When he learned that various spies had been uncovered thanks to Fury's actions at S.H.I.E.L.D., he dismissed the problem, as he managed to uncover Loki's Scepter, which he planned to use to further HYDRA's agenda.
He also revealed his intentions of burying all the deceased HYDRA agents "so deep that their ghosts can't reunite with their bodies," and that he intended to have Scarlet Witch and Quicksilver, whom he had retrieved earlier, for an important role due to their having their "age of miracles".
Avengers: Age of Ultron
Strucker was stationed at Sokovia experimenting with Loki's scepter when Avengers arrived and attacked his fortress. As the Avengers overpowered their soldiers, List asked him to send the Maximoff twins to fight against the Avengers, he forbade sending them as they were not ready for a fight. However, minutes later the twins left the base to fight.
Strucker told his men not to surrender before telling List that they should surrender and flee with the data to continue their work. When the Avengers broke into the base, Strucker was confronted by Captain America, who recognized him as the great criminal of HYDRA. Rogers was attacked by Wanda Maximoff when he was ready to capture Strucker. However, Rogers quickly recovered and knocked out Strucker by hitting him in the face with his shield. After being captured, he was handed over to NATO.
Shortly after, Ultron broke into Strucker's cell, demanding to know where he could find some Vibranium. Strucker fearfully informed that a fellow weapons dealer named Ulysses Klaue has shipments of Vibranium, and Ultron proceeds to kill Strucker by banging his head on the wall, painting the word "PEACE" on the prison wall with Strucker's own blood as a message to the Avengers, much to their horror.
Being the current leader of HYDRA, he is the employer of a man named Dr. List (who was the main antagonist in season 2 of Agents of S.H.I.E.L.D.) and therefore the of the season. This was revealed in "The Dirty Half Dozen", which serves as an arc weld into the movie itself. Though he doesn't appear physically, he is mentioned several times throughout the episode. In "Purpose in the Machine", it is revealed that Strucker has a son named Werner who is now working for Ward.
A different Baron Wolfgang von Strucker voiced by Kai Wulff appears in the video game Captain America: Super Soldier. This version of the character was born into Prussian nobility with familial association to the secret society known as Hydra. Ambitious, arrogant and harboring a particular distaste for the lower-class, Strucker quickly rose through Hydra, becoming proficient in both combat and tactics. Intercepted documents suggest he is pursuing development of advanced weaponry known as the "Satan Claw" for personal use. During World War II, in the mountains of Bavaria, Captain America encountered him in a tower where a radio dish controlling a powerful cannon is located. Captain America engaged Strucker in combat and, after a deadly battle, managed to defeat him. However the cannon lost control after the radio dish was destroyed and shot down the aircraft transporting the Howling Commandos. After they bailed out the plan, the cannon headed straight for the tower Strucker and Cap were in. Strucker, in a last-ditch attempt to take down Cap, charged at him, sending both Cap and Strucker flying off as the plane destroyed their battleground. As Captain America and Baron Strucker free-fell off the tower, Baron Struck managed to knock out Captain America, and he was last seen laying on the ground unconscious. Later, one of the Hydra personnel said that his recovery would take months. As of the events of Captain America: The Winter Soldier, this version of Baron von Strucker is no longer considered canonical.
Baron Strucker is similar to Professor Zündapp from Cars 2: Besides sharing the same voice actor, they both wear monocles, they are leaders of a faction, and they have both have the same first name (Wolfgang). They are also scientific geniuses.