Following on from the Rolling Stones documentary Crossfire Hurricane, documentary filmmaker Brett Morgen now focuses his attention on his latest subject; the enigmatic Nirvana frontman Kurt Cobain.

We sat down with the director to discuss why Cobain inspired him to making Montage of Heck, and whether he himself was a big fan of the band. He also explains why drummer Dave Grohl isn’t featured in the movie, and how essential it was to portray his subject in such a brutally honest, candid light, depicting the more flawed aspects to Cobain’s life.