Brian Tyree Henry and Aaron Taylor-Johnson have both commented on the fast-paced action film's similarities and differences with the Marvel Cinematic Universe.
Both actors played Phastos in Eternals and Pietro Maximoff/Quicksilver in Avengers: Age of Ultron, and appear as two closely related henchmen on Bullet Train.
"Both have their limitations," Henry told Digital Spy about comparisons with Bullet Train and the MCU.
"It's just not going to make the cut," he joked.
"I think that the character development for both of these worlds is very important. You want to have a connection with these players that you play, and you want people to care about these players that you play."
Lemon and Tangerine are played by him and Taylor-Johnson as well as some not-so-benevolent fellow assassins on a train from Tokyo to Kyoto. It was a "very collaborative" process, according to Henry.
"I think [director] David Leitch was quite open to what we brought to the table about what we considered to be the stories of Lemon and Tangerine," he said.
"We really wanted to lean into that, that brotherhood, and recognize that it came from a past." Taylor-Johnson echoed his co-star's sentiments.
Bullet Train was a unique challenge for its actors, who were asked to demonstrate their combat skills in a limited, sometimes quiet setting.
"You've already got a limited space and then you're fighting between tables and chairs, and then David Leitch says, "Actually, you and Brad [Pitt] are in the quiet cart and that woman's going to get really pissed off at you, so you've got to kill each other and not make any noise."
"It adds layers and layers, and that's what makes this system so enjoyable."
Bullet Train features Brad Pitt, Joey King from The Kissing Booth, Sandra Bullock, Andrew Koji from Peaky Blinders, and Deadpool 2's Zazie Beetz, among others.
Bullet Train is released on August 3 in UK cinemas, and on August 5 in US cinemas.