Last night, Legion's devastating "Chapter 24" saw the true cost of David Haller waging a war — Lenny's life.

Even with time travel at play, not everyone gets David's desired do-over, nor do they all want one. In "Chapter 23," the Time Eaters forced Lenny to live through her unborn daughter Violet's entire life from birth to death. Grieving over the loss of both her partner Salmon and their daughter, she rebukes David's offer to relieve her pain stating she needs to "feel" it.

Last night, still unable to process the grief, and finally fed up with David's narcissism, Lenny proclaimed she was better and good, but David ruined it all. In a startling move, she rebuffed David's plea to help him retrieve Switch and to change the past, and in her final act, killed herself and refused to let David get his way, defending her death. Despite feeling grief and rage, David does not seem to accept any fault for Lenny's death, in fact, David views her death as another person who abandoned him.

At the Legion Season 3 premiere, Marvel.com asked Aubrey Plaza, who plays Lenny Busker, about seeing this other side to Lenny, that grief, and more.

"I was excited to show a more vulnerable side of her," revealed Plaza. "Up until now, she’s been a wild child who doesn’t want to be strapped down by anything. Now she’s found the love of her life and she’s almost ready to settle down, in a weird way. But of course that plan gets hijacked."

"It was a really hard one for me," said Plaza, speaking on the life and death of Lenny's child. "It was really traumatizing. It was sad and a very horrific sequence, and I’m glad it’s over."

Echoing Lenny's final statements to David in last night's episode, Plaza stated, "The final season is the closest we get to Lenny’s ideal, kind of aspirational self. We find her in a place where she’s more at peace than she has been in the last seasons.... This is the closest to her true self."

On finally becoming her own person and ending her life on her own terms, Plaza shared, "Her entire existence is so based on David Haller; he’s been her entire reason of being for so long, and I think that what she does at the end is an attempt to take control back, take her power back."

"It’s very dissatisfying and depressing if she had just been killed by the Shadow King or by David or anyone," added Plaza. "She’s already died multiple times, she’s been tortured, and she’s been fighting to survive. It’s kind of her attempt at taking control, and saying, 'If I’m gonna die again, then I’m gonna die like this, and I’m gonna do it on my own terms.' Because she’s had enough."

Watch ‘Legion’ Mondays at 10:00pm ET/PT on FX.

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