'Bullet Train' director explains how he pulled off the surprising A-list cameos in the movie

• Warning: Major spoilers below if you haven't seen "Bullet Train."
• David Leitch revealed to Insider how he pulled off the major surprise cameos in the movie.

Since making "John Wick," director David Leitch hasn't just elevated the action-movie genre with movies like "Atomic Blonde," "Deadpool 2," and "Hobbs & Shaw," but he has also given us some amazing cameos along the way.

"Bullet Train" is no different.

Some fun A-list cameos pop up throughout the new action-comedy, which stars Brad Pitt as a hired killer named Ladybug whose latest job has him boarding a train from Japan to Kyoto to obtain a briefcase.

It's a trend that has been going on in Leitch movies since "Deadpool 2" when Pitt was revealed to be the Marvel character Vanisher, who, like the rest of the X-Force team, faces a gruesome death in the movie.

"Fast & Furious Presents: Hobbs & Shaw" kept the surprise cameos coming when Kevin Hart shows up for a hilarious interaction with lead stars Dwayne Johnson and Jason Statham.

Now in "Bullet Train," Leitch leveled up again by giving us two very surprising and high-profile cameos.

Channing Tatum plays a train passenger with a kinky side that we come across a few times in the movie and who delivers some great laughs.

Then later in the movie, the mysterious Carver is revealed. (In the movie, the name Carver is mentioned a few times. He's the assassin who was originally supposed to be on the job but had to cancel at the last second, which leads to Ladybug getting the gig.)

When the flashback-filled backstory comes to its gripping conclusion, we learn that the whole job was orchestrated to get Carver on the train.

In a shot filled with explosions, we find out Carver is played by none other than "Deadpool" star Ryan Reynolds.

Leitch told Insider that all of these cameos were able to happen because of his and his cast's relationships with various stars in Hollywood. A phone call can pull off a quick one-day's work.

However, Leitch noted that in Reynolds' case, he also made sure to remind the "Deadpool 2" star of his connection to Pitt.

"I just pitched him the idea of, 'Why don't you pay back Brad for the cameo in "Deadpool 2,"'" Leitch said. "That's really all it took. He was like, 'I'm in.' He was really grateful that Brad did that for him so he really wanted to support us on this."

Leitch said he's also come to really enjoy pulling off big cameos for audiences.

"When you pay your money and you go to the theater, you want to have a fun time," he said. "So looking at 'Hobbs and Shaw,' or the last 'Deadpool,' and this movie, cameos really work for me and I embrace them."

"I look for pockets of opportunity, we look for relationships with the actors on set," he continued. "If the material feels like it's right, I'm leaning in. You paid your money, you want to be surprised."

"Bullet Train" is currently playing in theaters.