Season 2 of The Boys secretly confirms another previous member of The Seven. With the return of The Boys on Amazon Prime Video, the next chapter in the conflict between The Boys and The Seven is continuing. Viewers first met Vought International's world-famous super team during season 1, but Homelander and his fellow Supes have a history that extends further into the past.
At the beginning of the series, Homelander saw Starlight become the newest addition to The Seven, joining a team that included Queen Maeve, A-Train, Black Noir, The Deep, and Translucent. By the end of season 1, A-Train was in the hospital, The Deep was on leave, and Translucent was dead. Season 2 is changing the roster again with the addition of Stormfront. However, these Supers aren't the only ones to ever be part of The Seven, and now season 2 has revealed another past member.
One aspect of Vought International's superhero enterprise is the Vought Cinematic Universe, a franchise of films based on Vought Supers, such as members of The Seven. During season 2 of The Boys, the team has a meeting about a new VCU movie in-development Dawn of The Seven, an origin story for the creation of the team. The meeting includes storyboards from the film's finale, showing Homelander, Queen Maeve, and other current members of The Seven. But, a hero that resembles Mister Marathon can also be seen, indicating that he was part of the team in the past.
This is the first reference to Mister Marathon in The Boys, but he is a previous member of The Seven in the comics. The former member had super-speed powers but died during one of The Seven's missions. He was clinging to Homelander when the leader of The Seven flew through an airplane, which did no damage to Homelander but killed Mister Marathon instantly. The death of Mister Marathon allowed for A-Train to take his place in the comics, so The Boys might have a similar history. With Vought's brand management, it wouldn't make sense for them to replace A-Train in the Dawn of The Seven with a different speedster unless that is how the team looked in the past.
The reveal of Mister Marathon being part of The Seven in the past is just another way that season 2 of The Boys is fleshing out the team's history. It remains to be seen if Mister Marathon will make a physical appearance through flashbacks, but one former member is confirmed to appear. Shawn Ashmore will appear later in the season as Lamplighter, a member of The Seven who was teased throughout season one. Lamplighter has a history with The Boys, which will surely be explored in more depth, and perhaps this reference to Mister Marathon is setting up his connection to them as well.