In early 1998 Denis’ first professional engagement was producing string arrangements for the band ‘The Prayerboat’ on their internationally critically acclaimed album ‘Polichinelle’. He went on to perform keyboards for the band as a guest musician over the next two years. Around this time Denis started composing music for film projects. His work includes His and Hers (Venom films), which won best documentary feature at the 2010 Irish Film and Television Awards (IFTAs); Undressing my Mother (Venom films), a multiple award winning film, including a European Academy Award; and Useless Dog (Venom films) for which he won best soundtrack at the 2005 European Short Film Biennale in Stuttgart. Denis’s television work includes The Limits of Liberty (South Wind Blows) performed by the RTÉ Concert Orchestra, the Barry McGuigan story In Sunshine or in Shadow (Fastnet Films) and An Treaty 1921 (Fastnet Films) which examined events in the three days leading up to the signing of the Anglo Irish treaty in 1921.
It was also around 1998 that Denis composed music for his first play: Theatre of the Unimpressed’s production of Tennessee Williams’ The Glass Menagerie in the Crypt Arts Centre in Dublin Castle. Since then Denis has composed music for over one hundred theatre productions and in 2011 won the Irish Times Theatre Award for his work on Sodome, My Love (Rough Magic). In 2008 Denis was an associate artist of the Abbey theatre. Recent theatre highlights include Man of Valour for The Corn Exchange (2011), The Resistible Rise of Arturo Ui for the Abbey Theatre (2008), Don Carlos for Rough Magic (2007), Festen at the Gate Theatre, Dublin (2006), and Titus Andronicus for Siren Productions (2005).