The Boys star Erin Moriarty opened up about her experience filming the final season of the hit Prime Video series while unknowingly battling complications that arose from Graves’ Disease.

The actress spoke out after this week’s episode of The Boys Season 5 gave Moriarty’s character, Annie January, some much-needed closure after she reunited with her father, who she thought abandoned her as a child. Moriarty revealed in a post to her Instagram Story that she was badly injured and experiencing health issues while filming her portion of the episode before she was diagnosed with Graves’ Disease.

Moriarty shared a photo of her bandaged knee to her Instagram Story, writing, “Okay, so: season 5, episode 4 of The Boys is one of the most important episodes I’ve ever shot. Unfortunately, that part of the season coincided with my health issues peaking before my diagnosis. I’m saving you the gnarly part of this picture but not long after this episode, I started to lose the ability to walk. The numbness in my feet led to a lot of falling. The night before we shot my segment of this episode, I fell and shredded up my knee.”

She wrote that she “barely” took any footage behind the scenes while filming the fifth and final season of The Boys, “especially as things worsened.”

Moriarty added that she wanted to share her experience battling Graves’ Disease.

“This isn’t a pity post. It’s mostly to say: f— autoimmune disease. F— it so hard. F— the ignorance surrounding it, too. I can’t remedy that ignorance but not being outspoken about it occasionally, feels wrong,” she wrote.

Moriarty was diagnosed with Graves’ Disease last June while filming her final moments as Starlight. While speaking with The Hollywood Reporter, the actress confessed she was “really, really, really struggling to get through it all.”

“I was starting to feel so ill, and even though I come from a family of doctors, no one thought to say, ‘Go get your levels tested,'” she recounted. “So it did lead to me not being as present for Annie during this final season as I would’ve hoped, and that was super painful for me. It was like I was offline for the first six to seven episodes, and then I came back online. I finally felt present at the very end of Season 5.”

Moriarty added that she doesn’t plan to watch this final season of The Boys “because it’s really important for me at this moment in time to put my psychological health above all other things.”

Graves’ Disease is an autoimmune disease that affects the thyroid gland, causing it to produce too much thyroid hormone. It can lead to lethargy, weight loss, eye conditions, tremors and more, according to Mayo Clinic.

The actress has become a lightning rod for controversy on the show, facing criticisms from viewers for her looks and her character’s decisions. Some even called this week’s episode – which serves as a turning point for her character who has become increasingly disillusioned since Season 4 – unnecessary “filler”. But, as Moriarty pointed out to THR, Annie’s reunion with her dad “gave her exactly what she needed in this episode to keep going.”

“He really galvanizes her and catalyzes her to find herself and her heroism for the remainder of the season,” she said.

Despite the difficulty she had filming this season, Moriarty shared she is still “excited for the audience to see the finale.”

“I think the audience is going to be so immensely satisfied by the finale. I never like to give a resolute prediction like that, and I never have, but I’m saying it now because I have so much excitement and confidence in it,” she said.

New episodes of The Boys air Wednesdays on Prime Video.