You tried to hide your suit from me? Now, it's gonna blow up in your face and destroy everyone you care about.
~ Darren Cross to Hank Pym.
Darren Cross, also known as Yellowjacket, is the main antagonist of the 2015 Marvel film Ant-Man.
He used to be Hank Pym's former assistant until he forced him out of his own company and took Pym's place as CEO. Since then, he has been planning to revolutionize the future of warfare and espionage with an advanced weaponized version of the Ant-Man Suit: code named the Yellowjacket.
He was portrayed by Corey Stoll, who also played Zev Vendel in Bourne Legacy.
Assistant to Hank Pym
Darren Cross graduated from MIT as valedictorian at the age of twenty. He was hired directly from MIT by Hank Pym, and for a time worked as his assistant. However, he wanted to learn the secrets of Pym's Ant-Man Suit and his size-reducing Pym Particle technology, only for Hank to repeatedly shrug off his curiosity and insist that no such thing existed. Cross became obsessed with proving the Pym Particle existed and at some point, he forced Pym from his company, Pym Technologies, and took over as CEO, renaming it Cross Technologies. Ever since he put all of his efforts towards re-discovering the Pym Particle.
In the film, Darren shows Hank his new project: a weaponized version of the Ant-Man Suit, codenamed the Yellowjacket. Which he wants to spread around the world to revolutionize the future of warfare by selling the suit to the highest bidder. However, he has yet to replicate the Ant-Man's Pym Particle technology into the prototype so that it's safe for human use, as it degenerates the cellular structure of living organisms, turning them into a pile of lifeless genetic material. Hank, horrified at the danger the new suit poses, chooses prisoner Scott Lang to become the new Ant-Man and steal the Yellowjacket from Cross before it is perfected and unveiled to the world.
Eventually, Cross finally duplicates the Pym Particle technology into the Yellowjacket, albeit an imperfect version that drives the user insane when worn for too long. However, Cross does not realize this, thinking he perfected the suit, and visits Pym at his house to gloat and kill him. However, he is unable to do so when he realizes his assistant, Pym's daughter Hope van Dyne, is also present. Realizing his former mentor might intend to use his own Ant-Man Suit to stop him, he instead invites Pym to the unveiling ceremony to prevent him from doing so, while also increasing security.
When Ant-Man breaks into Cross Technologies and attempts to steal the suit, he is instead captured by Cross, who reveals he knew about their plan and intends to sell both the Yellowjacket and Ant-Man suits to HYDRA, represented by former S.H.I.E.L.D. agent Mitchell Carson, while maintaining the monopoly on the particle used to fuel the suit. He then shoots Hank in the chest but Hank survives. When Ant-Man breaks out of the trap, Cross attempts to escape in a helicopter with the Yellowjacket; but Ant-Man follows him as Cross Technologies and it's research is destroyed by bombs planted by Ant-Man earlier.
With no alternative, Cross dons the Yellowjacket suit and fights Ant-Man inside the helicopter, eventually dueling in a briefcase which falls out of the helicopter, landing in a pool. Rising from the water, Yellowjacket is about to attack the owners of the house, but is incapacitated by Ant-Man, who swats him into a bug zapper. However, Ant-Man is arrested before he can destroy the Yellowjacket suit. Enraged at Scott for losing his company and driven insane by the imperfect shrinking formula, Cross arrives at Scott's home and attempts to kill his daughter Cassie, but is stopped by Ant-Man and Paxton. After a fierce fight with Ant-Man, Yellowjacket prepares to kill both Paxton and Cassie, but Ant-Man defeats him by shrinking to subatomic size and sabotaging the wiring in the Yellowjacket suit, causing Yellowjacket to shrink uncontrollably until he is ripped apart.
I'm gonna show you just how insignificant you are.
~ Yellowjacket to Ant-Man.
Darren Cross is an extremely cruel, ruthless, and uncharitable businessman who is willing to use Hank Pym's Pym Particles as a weapon. He believes that his ends justified the means and would easily attempt to use anything in order to gain his final goal of miniaturizing organic matter, including using lambs to shrink even if the end result was a failure and once this was accomplished Cross had no qualms about flicking the successfully shrunk lamb in its container as a mere plaything. He was a good person when he started working for Pym as his protege, but that changed when Cross became obsessed with the Pym Particles and the Ant-Man Suit. As Pym pointed out, Cross was basically what Pym used to be like in his youth and originally thought he was the son he never had.
The process is highly volatile. If one isn't protected by a specialized helmet, it can affect the brain's chemistry. I don't think Darren realizes this, and, you know, he's not the most stable guy to begin with.
~ Hank Pym to Scott Lang.
Cross had no problems with murder, as he killed Frank for questioning the Yellowjacket Suit's safety using a Shrink Gun, attempted to kill Pym out of jealousy and anger, and Cassie Lang and Jim Paxton when they got in the way. He was also willing to sell the Pym Particles and Yellowjacket Suit to shady businessmen - like HYDRA. As an extremely cautious and intellectual man, he was able to deduce and plan ahead of his enemies, like when he set a trap for Scott Lang, Pym and Hope van Dyne after the latter attempted to steal his suit. As Yellowjacket, he became crazy after losing Pym Technologies and being electrified by a fly-light trap. He attempted to kill Ant-Man with no restraint, as he unintentionally killed his bodyguards and the pilots during the helicopter fight with no regard for his own action, and was willing to use Cassie Lang as a hostage to get to her father.
Powers and Abilities
Size Alteration: Using the original Ant-Man suit and Pym Particles formula as a template, Cross can reduce approximately to the size of an ant. He also still maintains his regular sized strength and durability when shrinking due to increased density and compressed energy and physical force caused by size transformation.
Enhanced Strength: The suit grants Cross superhuman strength while shrunk. This is thought to be due to Pym Particles enhancing density and compressing energy and physical force to the user, giving him the power of a bullet. In the case of the Yellowjacket, its mechanisms may be able to enhance physical strength and resilience, even in human size, he was almost able to crush Ant-Man between his hands while Lang was in shrunken form. Though Ant-Man in normal size was able to take on Darren Cross while the latter was in the Yellowjacket suit.
Flight: Cross has the power of flight through highly advanced jets installed in the backward of the suit. The two top tentacle-like 'stingers' on the suit's back have exterior thrusters at the bottom of the tentacle that allow him to levitate and move forward with its propulsion.
Energy Pulse Stingers: The suit has four mechanical tentacle-like "stingers" on the back, the bottom pair of which can form shoulder weapons and direct energy weapons, which can fire intense energy blasts. The energy beams are blue and laser-like, burning through objects and, when Cross is in a small size, he can easily kill targets, much like bullets. When in normal size, the larger beams can easily burn through and destroy objects as large and as thick as a wall.
Genius Level Intellect: Darren Cross graduated from MIT at only twenty years old and was impressive enough to be recruited by genius Hank Pym to work for him.
Master Scientist: Cross was recruited by Hank Pym to work at his company, Pym Technologies as his personal assistant and one of the lead scientists. Over time, he became obsessed with replicating Pym's Ant-Man Suit, and managed to create his own version, the Yellowjacket Suit.
Expert Businessman: Cross was able to oust Pym from Pym Technologies and become its leader. Though the company had not presented a product in some time, Cross assured, in an interview that its shareholders were satisfied.
In the original comics, it is Hank Pym who is Yellowjacket after giving up the Ant-Man mantle to Scott Lang & Darren Cross in turn is a separate villain who had no association with the original Ant-Man, who happened to be Scott Lang's first enemy.
The Yellowjacket Suit was partially inspired by Eric O'Grady's Ant-Man Suit in the comics. Eric O'Grady is the third person to inherit the Ant-Man mantle, after Hank Pym and Scott Lang.
The Yellowjacket Suit is named after a Yellowjacket wasp, the common name in North America for predatory wasps of the genera Vespula and Dolichovespula, that are known simply as "wasps" in other English-speaking countries.
The Killer/Purple Man also has a similar death. He also has insane death screams and was crushed by his suit.
Despite that Cross is introducing the Yellowjacket suit for Mitchell Carson and HYDRA representatives and mentioning its name, the mentioning is brief, because Cross didn't adopt the alias of his suit just as Hank did with the Ant-Man suit.