Mary Holt used to have a reputation at work, she says, for “being unusual, creative and connecting with people”. It served her well in her career as an account manager for an advertising company. She was productive, well liked by colleagues and senior managers.

Yet her peers had no idea of her private anguish. “I had peaks and valleys in my moods,” she says, asking that her real name not be used. “I could be walking down the street on my way to meet my friend feeling happy and then two blocks down I could be overwhelmed by a feeling that I should kill myself.” During the euphoria, she felt she was “touching the hand of God”, feeling capable of curing cancer one minute, before hatching plans to launch a Hollywood career. Self-medication was her way of managing these manic phases – Valium in particular. During the lows she would get through the day by making a series of pacts with herself: “If I just made it through to the end of the meeting, I could kill myself then.”

The World Health Organisation suggests that “one in four people in the world will be affected by mental or neurological disorders at some point in their lives”. Last year, it produced a report on mental health that found “the vast majority of people with mental health conditions would like to be employed but stigma, discrimination, and lack of professional experience prevent them from doing so”.