Hannan's work as a playwright has been produced by the Royal Shakespeare Company, the Old Vic, Shakespeare's Globe and the National Theatre of Scotland.

His latest work - an adaptation of George Orwell's Nineteen Eighty-Four - opens in August 2026 at the Citizens Theatre Glasgow and will tour to the Lyceum Edinburgh, His Majesty's Aberdeen and Dundee Rep.

He has produced multiple award-winning plays spanning five decades.  His 2016 play What Shadows - an exploration of identity politics focused on Enoch Powell's 'River of Blood' speech - premiered at Birmingham Rep and was described by the Daily Telegraph as 'the most provocative theatrical act of the decade'. It toured to The Park Theatre in London and The Lyceum Edinburgh in 2017 and was translated into French in 2021 as Ce Que Les Ombres.

Shining Souls opened at the Traverse Edinburgh in 1996 and was revived by the Old Vic in 1997, winning a Lloyds Bank Playwright of the Year nomination.  The Guardian described the central character as 'a kind of Mother Courage cum Marilyn Monroe' and called the play 'a funny and serious postmodern masterpiece'.  

Elizabeth Gordon Quinn opened at the Edinburgh Traverse Theatre  in 1985 and was revived in 2006 by the National Theatre of Scotland in its inaugural season. The Guardian described the protagionist as 'a Marie-Antoinette of the slums' and a 'monstrous and magnificent heroine'.

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