|“||I was partners with Hank on a project called G.O.L.I.A.T.H..||„|
|~ Foster talking about his former partnership with Hank Pym.|
William Barrett "Bill" Foster is a major anti-villain in the 2018 superhero film sequel Ant-Man and the Wasp. He is a former colleague of Hank Pym and the surrogate father of Ghost.
Bill was a biochemist who was a former colleague of Hank Pym, having worked alongside him with Project G. O. L. I. A. T. H.. At some point in time, he was introduced to a young Ava Starr, who had lost her parents when her father Elihas Starr attempted to continue his experiment in spite of being discredited by Hank for stealing his particles. Ava survived the explosion, but her body cells were gravely split in half, giving her the ability to phase through objects, but at the cost of her slowly dying because of it. Bill had since become a surrogate father for her and had spent a duration of his life finding a cure for her condition.
Bill was able to build a special chamber that feeds quantum energy into Ava to somewhat stabilize her molecules and keep her solid. However, Bill discovered that Ava's illness will continue to worsen over time and the chamber can only do so much to slow down her imminent death, forcing the two to look for more drastic measures to save Ava.
Meeting Ant-Man and the Wasp
Scott Lang, Hope van Dyne, Hank Pym visit Bill looking for assistance to find Pym's portable lab which Ghost stole. Bill remains antagonistic towards Hank but offers some advice to track down the lab. The three were captured by Ghost, and Bill reveals himself to be working with her. The two plan to use the Quantum Tunnel in the lab to extract quantum energy directly from Janet so Ava can be stabilized, however, the process will most likely kill Janet. Bill is willing to take that risk as he still cares for Ava. Despite being more than willing to steal his former colleague's technology, he immediately berates Ava on her suggestion to abduct Scott's daughter Cassie.
As Lang and Hope were forced to fight off Sonny Burch and his men from stealing the lab, Ava successfully recaptures the lab and begins to perform the experiment on herself. When Bill attempts to speak her out of this, Ava rashly throws him across the room. While Ant-Man and the Wasp fight Ghost, Hank Pym confronts Bill and forces him to retreat, though he also promises to save Ava's life once Janet is rescued. Bill cautiously decides to trust Hank and leaves the shrinking lab as Hank takes the ship into the Quantum Realm.
Pym and Janet return from the Quantum Realm, and Janet heals Ava's ailment by giving her some of her quantum energy. As Ava was attempting to escape, she suggests to Bill that he leave her because he hadn't committed any crimes she had done through S. H. I. E. L. D., but Bill refuses to leave her side as he still cares for her. The two embrace before they both escape the authorities. Though it would have seemed that Bill has achieved his intent in curing Ava, it turns out that the cure is temporary as Lang and the Pym family are working on the quantum realm to find a more permanent solution for Ava's condition.
Despite allying with the villainous Ava, who he deeply loved and considered a daughter to the point of tolerating her ruthlessness, Foster in contrast is a good-hearted and kind and affectionate man who regretted the violence that had to be done to save his daughter and he was quick to befriend Ant-Man, treating him kindly even when he had him captured and allowing him to communicate with Cassie. Despite caring about Ava, he still has his limits, as he refused without hesitation to get Cassie involved, threatening to abandon his contribution if Ava even laid a finger on her. Despite his distaste of Hank, was on good terms with Janet, having outright stated he warned Janet against tangling with Hank and regretting his failure that caused her to be trapped in the Quantum Realm. Foster also took the time to find ways to extract her energy without killing her and even hesitated at the end of it to fully extract her Quantum Energies, believing it would kill her. Additionally, even with all his resentment towards Pym, Foster never wanted him dead and protected him from Ava's wrath; he was concerned when he feigned a heart attack, showing that regardless of all of their past, his friendship with Hank wasn't completely gone yet. They ultimately achieved a reconciliation of sorts, with Foster trusting Hank to uphold his word on finding a way to save Ava and sincerely wished him good luck.
- Genius Scientific Intellect/Master Engineer: An exceptionally intelligent scientist on the same level as Hank Pym, with Hank considering him his rival, Foster has a solid quantum technology background, having worked along with Hank and Janet when they were in SHIELD as one of it's foremost scientists, and likewise extremely knowledgeable and adept in quantum lore and other fields of science, being a well-regarded professor of Berkeley University after SHIELD's collapse, teaching Biochemistry and Quantum Science. He along with Hank were able to succeed in Project GOLIATH, with Foster growing 20 feet. Foster was also able to quickly completely analyze Ava's problems as being Quantum Instability and likewise able to build means to help her slow it's process, building her Ghost suit for more refined control over her powers and slight pain reducing and Quantum Energy Chamber to momentarily stabilize Ava. Though he could not devise a means to cure her on his own, Foster was scientifically competent enough to correctly deduce that sufficient amounts of Quantum Energies could fix her and was able to develop the equipment to connect the Chamber to the Quantum Tunnel to harness Janet's energies, which would have worked had Ava not been stopped. Foster was also able to give correct assistance to Hank to track down his lab by using one of his suit's regulators.
- In the original comics, Bill was a superhero known as Goliath, who had the power to grow large in size (which is referenced through his mentioning of Project G.O.L.I.A.T.H., and how he had grown up to twenty-one feet in length).