Harvey Milk, played by Sean Penn, moves to San Francisco in the early 1970s and opens a camera shop in the Castro District, known at the time as a predominantly gay neighborhood. As Milk becomes more involved in the community, he realizes that the LGBT community has little to no political power and representation. Milk decides to run for a seat on the San Francisco Board of Supervisors and becomes the first openly gay person ever elected to public office.
Throughout his campaign, Milk faces opposition from the conservative establishment and the religious right, who use homophobic rhetoric to try to discredit him. Despite these obstacles, Milk is able to garner support from a diverse group of San Franciscans and win the election.
While on the Board of Supervisors, Milk fights for gay rights, as well as for the rights of other marginalized groups, including women and people of color. He co-sponsors an anti-discrimination bill, which becomes known as the "Harvey Milk Bill" and is eventually passed by the California State Legislature.
However, Milk's time in office is cut short when he and Mayor George Moscone are assassinated by former Supervisor Dan White. Milk's legacy as a trailblazing gay rights activist lives on, and he is remembered as a hero and inspiration to the LGBT community.