"A hunger strike? Who is she, Gandhi?" scoffs Mark Ruffalo’s exasperated politician when he hears that activist Judith Heumann has taken her occupation of a federal building up a notch. Being Heumann tells the story of the heroic lengths that the aforementioned disability rights campaigner and her comrades went to, simply to secure themselves, and those like them, a more equitable existence.

Writer-director Sian Heder follows up the triple Oscar-winning CODA with this adaptation of Heumann’s 2020 autobiography, Being Heumann: An Unrepentant Memoir of a Disability Rights Activist, with the script co-written by Rebekah Taussig. The film provides a plum role for British TV star Ruth Madeley, playing Heumann – a wheelchair user who contracted polio as a child.

It focuses on the 1977 Section 504 sit-ins, which piled pressure on the American government (particularly Ruffalo’s Secretary of Health, Education and Welfare, Joseph A Califano Jr), to act on disability rights legislation, which had the potential to transform lives.

Particular focus is paid to the San Francisco sit-in, a 26-day non-violent occupation, led by Heumann, who is accompanied by her rival Kitty Cone (Madeline Delp), right-hand man Ed Roberts (Michael Patrick Thornton), prominent Black Panther Brad Lomax (Antwan Tolliver), and other activists, played by the likes of Jon Beavers, Ray Fisher and Roberta Colindrez. Dylan O’Brien appears as a local TV reporter who is initially dismissive of the action, but embeds himself within the group after realising the significance of the story, while Rob Delaney plays a sympathetic congressman.

With its warm hues and lovely period design, Being Heumann tells an incredibly important story in a compelling and accessible way. The film movingly highlights the co-operation between different activists within the disabled community and beyond, including queer rights advocates and the aforementioned Black Panthers. It also shows the tensions that arise between them, for example on the issue of dropped kerbs – essential for wheelchair users, but more problematic for those who are blind.

Despite the couldn’t-be-more-serious stakes, it’s far from a dry or humourless portrayal of events. Heder and Taussig delight in details like the makeshift camp’s “sex tent” and play up the element of farce, showing how these activists quite literally can’t get arrested as there are no accessible jails, while Ruffalo’s politician often cuts an amusingly flustered figure.

The group’s cause is a tough sell in an unenlightened era – where smoking menthols, for instance, is still seen as “not smoking” – but the film highlights the intolerable status quo by illuminating a wide range of cruel and unjust personal circumstances. It shows how change is morally undeniable, even if the practical and financial challenges are seemingly insurmountable, with the latter causing Califano – who is proud of his record on civil rights – to drag his heels.

Being Heumann sometimes makes its points very powerfully, such as when Judith points out that the disabled are a minority that “anybody could be part of”, and when she challenges a reporter’s patronising use of the word inspiring. However, Heder and Taussig’s script doesn’t really do subtle, with a little too much in the way of broad, stirring soundbites that occasionally make it feel like it is spelling the issues out.

This lack of nuance can limit the actors, with characters’ shifts in stance sometimes clunkily and all-too hastily handled, for example in the case of an unexpectedly amenable Ruffalo, or a suddenly sympathetic O’Brien, whose reporter is presented at the outset as a comical douchebag.

However, Madeley makes a fiery focus. A sobering scene where we quietly witness the struggle of our heroine’s day-to-day existence follows one where we see her at her most vocal and influential; stripped of her agency, Judith remains stuck in bed one morning, desperately needing the toilet, because her carer is running late.

Nevertheless, Being Heumann doesn’t paint its protagonist as saintly or even especially likeable, and it’s all the better for it. We see how Judith’s willingness to be "the a**hole" and push people past their limits is necessary to affect change, even if the film emphasises just how lonely that can be.

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