Hanrahan is known for his raw on-the-ground approach to reporting, gaining access to difficult stories and embedding into dangerous communities across the world.

He covered paramilitary factions, criminal gangs, environmental militancy, civil unrest and dark web networks.

Hanrahan's work covering the Kurdistan Workers' Party (PKK), a Kurdish militant group, in southeast Turkey, landed him in prison.

He was arrested in September 2015 in Turkey with his colleagues Philip Pendlebury and Mohammed Rasool, after the three embedded with the PKK's youth wing, the YDG-H, who were actively fighting the Turkish Armed Forces.

[8] In 2018 Hanrahan founded the grassroots independent media platform Popular Front,[9][10] which consists of a podcast, documentaries and a magazine.

In a 2022 Complex magazine profile on Popular Front, Hanrahan was named "one of the most important voices in war and conflict reporting".

In 2022, Hanrahan made a documentary embedded with anti-fascist Ukrainian football hooligans who'd volunteered to fight against the Russian invasion as part of the Territorial Defense Forces.