One sunlit evening, May 6, 1882, Lord Frederick Cavendish and Thomas Burke, Chief Secretary and Undersecretary for Ireland, were ambushed and stabbed to death while strolling through Phoenix Park in Dublin. The murders were funded by American supporters of Irish independence and carried out by the Invincibles, a militant faction of republicans. A new spirit of goodwill had been burgeoning between British Prime Minister William Gladstone and Ireland's leader Charles Stewart Parnell, with both men forging in secret a pact to achieve peace and independence in Ireland - with the newly appointed Cavendish, Gladstone's protege, to play an instrumental role. The impact of the Phoenix Park murders was so cataclysmic that it destroyed the pact, almost brought down the government, and set in motion repercussions that would last long into the twentieth century.

From the adulterous affair that caused Parnell's downfall; to Queen Victoria's prurient obsession with the assassinations; and the investigation spearheaded by Superintendent John Mallon, also known as the "Irish Sherlock Holmes", culminating in the eventual betrayal and clandestine escape of leading Invincible James Carey and his murder on the high seas, The Irish Assassins brings us intimately into this fascinating story that shaped Irish politics and engulfed an Empire.