The online star with 15 million subscribers on demystifying everything from black holes to the immune system, the trouble with anti-vaxxers, and what his cancer taught him

Skim Philipp Dettmer’s CV and you’d have to say he was an improbable candidate to become one of the world’s foremost science communicators. The 35-year-old from Munich dropped out of high school in Germany aged 15. He eventually did a history degree, and only became involved in science through his interest in infographics. This led, in 2013, to him creating Kurzgesagt (AKA “In a nutshell”), one of the most popular science channels on YouTube. The platform’s irreverent, kaleidoscopic videos – stripped-back guides to everything from black holes to Covid – have more than 15 million subscribers and have clocked up almost 1.5bn views.

Dettmer has now written a book about the human immune system, which has intrigued him for more than a decade. Everyone has an opinion on theirs – whether it’s good or not up to much; how best to “boost” it – but it can be a struggle to understand how it works. In Immune: A Journey into the Mysterious System That Keeps You Alive, Dettmer uses eye-catching graphics and simple language to untangle the strange, compelling, sometimes grisly methods our bodies use to defend us from disease.