An Béal Bocht (The Poor Mouth) is a 1941 novel in Irish by Flann O'Brien, published under the pseudonym "Myles na gCopaleen".

One of the recurring figures of speech in the book is the line from Ó Criomhthain's An t-Oileánach, ...mar ná beidh ár leithéidí arís ann, "...for our likes will not be (seen) again"; variations of it appear throughout An Béal Bocht.

Both derive from a character named Myles-na-Coppaleen in Dion Boucicault's 1860 play The Colleen Bawn, which, in turn, comes from the Irish na gcapaillín, "of the little horses".

The narrator, after a series of bloodcurdling and horrible adventures, is eventually imprisoned on a false murder charge, and there, "safe in jail and free from the miseries of life",[5] finally has the chance to write this most affecting memoir of our times.

[8] Irish filmmaker Tom Collins adapted and directed an animated version of the book, which was first shown (outside of festivals) on TG4 on Christmas Day 2017 and features the voices of Owen McDonnell and Donncha Crowley.

The artwork was done by John McCloskey, whose graphic novel adaptation based on Collins' screenplay was published in 2012 by Cló Mhaigh Eo.