Erin Moriarty opens up about Graves’ disease struggle during filming of ‘The Boys’

The actress revealed she was diagnosed mid-production and experienced severe fatigue and recovery challenges

Erin Moriarty has spoken in detail about the physical and emotional impact of Graves’ disease while filming the final season of The Boys, describing how the autoimmune condition significantly affected her ability to work on set. The actor, who plays Starlight in the Prime Video series, revealed that she was diagnosed during production and experienced ongoing symptoms that altered her performance and day-to-day experience during filming.

Graves’ disease is an autoimmune disorder that affects the thyroid gland and can lead to symptoms such as fatigue, anxiety, insomnia, weight changes, and heart-related complications. Moriarty first disclosed her diagnosis publicly in 2025, noting at the time that treatment had quickly improved her condition after she initially experienced worsening symptoms she attributed to stress and exhaustion.

In her latest interviews with international entertainment press, Moriarty explained that the illness had a profound effect on her ability to remain present during filming. She stated that for part of the production she felt disconnected from her character Annie January and struggled with the physical demands of long shoot days. According to Moriarty, the condition led to periods where she felt unable to fully engage with her performance.

She said the diagnosis came several months into filming the final season and acknowledged that she initially believed her symptoms were related to general fatigue from work. Once she began medical treatment, she reported a rapid improvement in how she felt physically, although recovery during the production period remained uneven.

Moriarty also addressed the emotional strain of continuing work while managing a chronic illness. She described feelings of guilt about not being able to perform at the level she expected of herself, particularly given the demanding nature of the role and the expectations of a concluding season. However, she emphasised the importance of prioritising long-term health over professional pressure.

The actor has been vocal about autoimmune disease awareness, encouraging early medical testing for others experiencing similar symptoms. She has highlighted how easily the condition can be misattributed to stress or lifestyle factors, which can delay diagnosis and treatment.

Despite the challenges, Moriarty confirmed that she completed filming the final season and credited the cast and crew for providing support throughout production. She also shared that she has chosen not to rewatch the final season at this stage, explaining that focusing on psychological recovery remains her priority following a difficult period of illness and work.