WARNING: Major spoilers ahead for Deadpool 2.
Morena Baccarin’s character met a surprising fate in the film – taking a bullet very early on, and being shockingly killed off.
The move hasn’t been well received by some fans, arguing that it was amiss for the apparent female lead to meet a premature end.
But Leitch has defended the twist, saying it gave the emotional backbone that the sequel needed.
“I understand where [upset fans are] coming from,” he told ComicBook.com.
“As a filmmaker, I believe I have a record of strong female characters and proactive female characters.
“But with Deadpool it’s different. It’s Deadpool’s movie, and you need to take everything away from him to humanise him.
“He can be grating and he can be sort of offensive and he can be all these things, but you need an emotional hook that grounds the movie that we can go on this journey with this character and experience Deadpool.”
Pointing out that Vanessa returns in several later scenes, he added: “And quite frankly, she doesn’t leave the movie.
“She is a huge point of contact for him and learning his lesson in the world and learning that one of act of kindness can change history.
“And I think without her being the vehicle that he learns that from, I don’t know, it wouldn’t have been the same film and so we wouldn’t have had that emotional context.
“Even the scene at the end where they visit each other in the afterlife, hugely emotional, great performances by both of them. So, again, I don’t think she left the movie.”
Ryan Reynolds has also spoken out on a controversy – albeit a jokey one he made up himself.
Deadpool 2 is out now.