How 'Avengers: Endgame' Makes Good On An Unexpected Crossover Fans Have Wanted For Years

For years, Marvel Studios and Marvel TV have been touting the phrase "It's All Connected," but rarely have they lived up to that promise. Apart from a few references to "the event" in the Netflix shows like Jessica Jones or Daredevil, or cameo appearances from B-characters in Agents of S.H.I.E.L.D., the Marvel Cinematic Universe and the TV universe have remained largely separate. And as the years have gone by, they've branched further and further apart until it seemed impossible for the characters from the separate properties to cross paths. But that hasn't stopped fans from clamoring for a crossover between the MCU and Marvel TV shows.

But after years of demands, Avengers: Endgame delivered. An Avengers Endgame crossover finally brought together the MCU and Marvel TV, making good on that hashtag #ItsAllConnected.

Spoilers for Avengers: Endgame follow.

When Tony Stark (Robert Downey Jr.) and Steve Rogers (Chris Evans) travel back to S.H.I.E.L.D. headquarters in the 1970s in their second attempt to nab the Tesseract, they both run into a few familiar faces. For Tony, it's his dear father Howard Stark (John Slattery) and for Steve, it's his long-lost love Peggy Carter (Hayley Atwell). But little do they know that those two blasts from the past had one friend in common who was about to make his proper MCU debut: Jarvis.

Played by James D'Arcy, Edwin Jarvis made his debut in the ABC series Agent Carter, as the trusty butler to Howard Stark who teams up with Peggy on several espionage missions. In Avengers: Endgame, an older Jarvis appears alongside Howard Stark, opening the car door for the S.H.I.E.L.D. co-founder as Howard walked away from his intimate conversation with Tony about parenthood. "Have I met that man?" Howard asks Jarvis before he gets in the car. "You meet lots of people, sir," a perplexed Jarvis replies before closing the door for Howard.

With this appearance, Jarvis becomes the first character from Marvel TV to make his way over the MCU. But who exactly is Jarvis and why does he share the same name as Tony's beloved A.I.?

Jarvis first appears in all his gangly, buttoned-up glory in ABC's Agent Carter, which ran for two seasons from 2015 to 2016. The series starred Atwell as the titular Peggy Carter in the aftermath of World War II as she works as an agent to the Strategic Scientific Reserve, the government war agency that preceded S.H.I.E.L.D. In the first season, Howard Stark (Dominic Cooper, following up his appearance in Captain America: The First Avenger) finds himself framed for distributing weapons to enemies of the U.S. and enlists the help of Peggy to clear his name. He tasks Jarvis with aiding Peggy in this mission, and the two become fast friends.

Though it's never explicitly stated in the films or the TV series, Jarvis is a pivotal part of the Stark family who supposedly helps raise Tony following the death of his parents. At least, it's implied that he has a close enough relationship to Tony that he becomes the inspiration of the name of Tony's A.I. Tony even gives J.A.R.V.I.S. a British accent (Paul Bettany) that is not too far off from the original Jarvis' voice.

In the '70s, we get to see Jarvis still loyally serving Howard, though now sporting a flowing mane fitting of the groovy era. Was it just Jarvis' luscious locks that got him a cameo in Avengers: Endgame and not, say, any of the superheroes from Agents of S.H.I.E.L.D.? (Poor Clark Gregg couldn't even squeeze in a little appearance as Phil Coulson, who is arguably more important than Thaddeus Ross.) Maybe, but it probably had more to do with the fact that Agent Carter was the only Marvel TV series that had Marvel Studios chief Kevin Feige on as an executive producer.