Julius is an Olivier award-winning theatre producer and a Fellow of the Birkbeck Centre for Contemporary Theatre, University of London. The leading authority on Agatha Christie's work as a dramatist, he produced the 2001 Agatha Christie Theatre Festival (a 12-week season of Christie's complete stage works as then known), and in 2006 founded the Agatha Christie Theatre Company for Bill Kenwright Ltd. In 2012 he was invited to write the introduction to HarperCollins' 60th anniversary edition of The Mousetrap and Other Plays, and in 2015 HarperCollins published his book Agatha Christie; A Life in Theatre.
His numerous appearances as a speaker on Agatha Christie include the Oxford Literary Festival, the National Theatre’s ‘Platform’ series and the 2017 and 2019 Agatha Christie conferences. In 2017 he became the archivist for the historic production records of The Mousetrap. In 2020, he directed and co-adapted Agatha Christie’s unpublished play The Lie for Radio Four, and was awarded a PhD for his work on Christie’s plays by Goldsmiths, University of London. His latest book, Stars and Spies, co-authored with MI5’s official historian, Professor Christopher Andrew, was published last year by the Bodley Head and examines the links between espionage and show business.