[3][4] Leith studied at the Guildhall School of Music and Drama (2009–2015), where his teachers included Julian Philips and Paul Newland.
The title and concept for the opera were taken from the 2005 film of the same name by Gus van Sant, which was a fictionalised account of the last days of Kurt Cobain.
[12] The album was chosen as a pick of the week by The Guardian, who described it as having "moments of unexpected grandeur alongside sheer banality, yet somehow the mixture is curiously addictive.
[11] In May 2024, A. G. Cook’s third studio album, Britpop, was released featuring a two-minute track called Butterfly Craft, composed by Leith.
In 2020, he joined a crowd of protestors and posted a photo of himself brandishing an obscene gesture outside the family home of Dominic Cummings, following revelations that the latter had breached COVID-19 lockdown restrictions.