While daughter Frances Bean Cobain served as the project's executive producer, the Nirvana frontman's widow had no editorial input but did provide Morgen with access to her personal archives as a way of providing material and support for the first fully-authorised Cobain film.

Montage Of Heck - which includes unreleased songs by the Nirvana leader - had its world premiere at last month's Sundance Film Festival and just debuted at the 65th annual Berlin International Film Festival. It will see a UK release in April and US television premiere on cable network HBO on May 4.