Warren Ellis’s memoir, Nina Simone’s Gum, is about as weird as it sounds. For the last twenty years, Ellis, a rock musician best known for his long-term collaboration with Nick Cave, has acted as self-appointed ‘custodian’ of a piece of chewing gum spat out by Nina Simone during a concert at the Royal Festival Hall in 1999.

For two decades, Ellis has worried about and protected the gum, not daring to remove it from the white hand towel into which Simone originally gobbed it, or to look at it too much for fear of degrading it by exposure (‘I thought each time I opened it some of Nina Simone’s spirit would vanish’). The gum has assumed numinous significance in his life, like a secular relic or ‘totem’, an antenna for ‘invisible forces’. While for most of us getting attached to a piece of gum is a disgusting accident, for Ellis it set him on the path to spiritual transcendence.

The 1999 concert turned out to be Simone’s last in the UK. It is the event to which Ellis’s memoir continually returns. By then, Simone, her health declining, was living in semi-retirement in Aix-en-Provence. Ellis’s handsomely produced memoir includes emails, text messages and photographs provided by others present