As Shaker Aamer finally returns to the UK after 13 years in Guantánamo, Larry Siems, writer, human rights advocate and former director of the Freedom to Write and International Programs at PEN American Center, makes an impassioned plea for the case of Mohamedou Ould Slahi.

Read ‘#freeslahi: An appeal for justice’ here.

Watch the Guardian’s mini-doc on Guantánamo Diary.

Listen to John Hurt, Benedict Cumberbatch, Nick Cave, Neil Gaiman, Brian Eno, Nadya Tolokonnikova, Jude Law, Colin Firth, and many others read excerpts from Guantánamo Diary.

Read English-language reviews of Guantánamo Diary.

Guantánamo Diary is published by Canongate in the UK.