The Marvel Cinematic Universe has seen its characters change and evolve, but one of the biggest changes has been that of J.A.R.V.I.S. into Vision – and Paul Bettany knew about it long before it happened. Since 2008, the MCU has been bringing characters from Marvel Comics to the big screen (heroes, villains, and allies), and it all began with Jon Favreau’s Iron Man, which introduced Robert Downey Jr. as Tony Stark along with Favreau himself as Happy Hogan and Gwyneth Paltrow as Pepper Potts.

Iron Man also introduced a minor character that went on to have a much bigger role in the MCU: J.A.R.V.I.S., Tony Stark’s A.I. and personal assistant tasked with running business for Stark Industries and security for Tony’s house and Stark Tower. J.A.R.V.I.S. was voiced by Paul Bettany, and it became a character on its own, even if a minor one who was sometimes used to enhance the comedy of a scene. J.A.R.V.I.S. went through a major upgrade in Avengers: Age of Ultron, where it became corporeal and changed its identity to Vision, with Bettany also playing the role, and he had to keep the secret of this transformation for years.

Related: Iron Man 3 Hid A Massive Clue JARVIS Would Become Vision

Avengers: Age of Ultron was the second time the original Avengers teamed up and it wasn’t as exciting as their first adventure together, but the events of this particular movie have ultimately impacted the MCU years later. In it, Tony and Bruce Banner developed the A.I. peacemaking program “Ultron”, with the purpose of helping the team with their heroic tasks, but it all went wrong when Ultron decided that the real threat was humanity. Ultron destroyed J.A.R.V.I.S., but its remains were found by Tony, and after the Avengers stole Ultron’s synthetic vibranium body, he uploaded what was left of J.A.R.V.I.S. into it, and with the power of the Mind Stone, Vision was born. This transformation was a surprise to fans, but Bettany had known for a while that he was going to have a bigger presence in the MCU.

Vision is born in Avengers: Age of Ultron

Among the many secrets and stories shared in the book The Story of Marvel Studios is that of Bettany learning about J.A.R.V.I.S’ fate years before Avengers: Age of Ultron happened. The book reveals that becoming Vision “was a secret that Bettany had to keep for two years before it was officially announced in 2014”, meaning that by the time the first Avengers movie came out, Bettany knew J.A.R.V.I.S. wasn’t going to be around for longer, but he would. Vision has grown as a character and has been given a bigger role in the MCU even after his death in Avengers: Infinity War. By the end of Age of Ultron, he was part of the New Avengers team along with Wanda Maximoff (Elizabeth Olsen), War Machine (Don Cheadle), and Falcon (Anthony Mackie). Vision developed a romantic relationship with Wanda, but it didn’t have a happy ending as he was killed in Avengers: Infinity War when Thanos took the Mind Stone.

However, Vision was given a second chance in WandaVision, where he not only returned as a projection of Wanda's mind but a new Vision – White Vision – was made with the remains of the original one, thus extending Bettany’s time in the MCU. Although the minds behind the MCU have a plan, this one is constantly changing depending on various factors, including the characters’ development and how well-received they are. Going from J.A.R.V.I.S. to Vision was a big change for Bettany and the MCU, but it has turned out for the better, and it’s to be seen what White Vision’s role will be.

Next: How JARVIS Showed Iron Man’s Biggest Problem

Key Release Dates