Brían F O'Byrne, best known for his role as D.I. Mick Moynihan in Love/Hate, will join the cast of the American Civil War drama series Mercy Street.

The Irish actor will again appear in a similar role as a law enforcement officer in the show's second season. His character is described as a Scottish man named Allan Pinkerton, who's the head of the Union Intelligence Service.

Director Ridley Scott is an executive producer of the show. Series 2 examines the growing chaos in Alexandria, Virginia, a boarder town between North and South. The season will focus closer on the fighting between the the Confederate and Union armies.

I spy Allan Pinkerton (@brianfobyrne) - head of the Union Intelligence Service. #EffectiveDetective #MercyStreetPBS pic.twitter.com/nkxpz0Paez

— Mercy Street PBS (@mercystreetpbs) April 26, 2016