'A Brimful of Nettle' is an expression that states that whatever situation you find yourself in, and that situation rings on far too long, and now, your cup is full to the brim and overflowing of any understanding of it, and a brimful of nettle being not only an annoyance, but generally a situation that angers you. Consider the situation the Siringo family has found themselves in. They have lost the patriarch of their family, Richard Siringo, to a heart attack, and yet, the trouble with Devlin Wade continues. The Irishmen, Flynn McDonagh, Seamus O'Neil, and Casey O'Connor who belong to the Fenians of Ireland, who are buying guns, and even recruiting help from men of the United States, namely, Clancy Burrows, to help rid their country of British rule. In that effort, they bought weapons from a well-known gun runner named Brass Tacks who now want those guns back. Those weapons will bring a lot of money from either the North, or the South should a shooting civil war break out. So, because of that, the Irishmen are on the run from Brass Tacks, and his gang of cutthroats. They are doing their level best to get those guns to Matagorda on the coast for transport to Ireland. Then, there is the unfortunate circumstances that 1st Lieutenant Jamie Carlson has found himself after the Comanche ambush near Lake Texoma in North central Texas that wiped out nearly all of his company forcing Jamie to command a haphazard detail of wounded troopers on foot to the town of Whitesboro, Texas, ten miles southwest of the ambush site to a town doctor to give aid to the troopers who have survived the massacre. Colonel Mackenzie of Fort Richardson has been notified by Sergeant Major Del Dickerson of that detail upon arrival of Whitesboro. Plus, there are twists and turns that increase the excitement as well as the entertainment.