Lili Ilse Elvenes (*1882 Denmark–†1931 Germany) was one of the first transgender women who ultimately died from on a series of risky and essentially unproven operations to remove her male parts and transplant female reproductive organs. Her remarkable life history – made into ‘The Danish Girl’ and the learnings thereof – carries important messages about how we, citizens and doctors alike, should deal with hormonal conditions. There are instructive parallels with other disorders, for example, insufficiency of the thyroid gland.