Maxwell responded to news of the massacre at Setlik III, wherein his wife and children were killed. He arrived the day after most of the inhabitants were killed, and sent away teams to protect the remaining people in the more remote regions.
In 2367, Captain Maxwell, believing the Cardassians to be re-arming and re-equipping themselves, undertook his own unauthorized preemptive strike, beginning with the destruction of a Cardassian outpost in the Cuellar system which Maxwell believed to be a military supply port disguised as a science post. He then turned to any supply vessels heading for the outpost. The USS Enterprise-D was ordered in pursuit. Maxwell destroyed a supply vessel and a nearby Cardassian warship, killing approximately six hundred-fifty Cardassians, despite it being given the Phoenix' prefix code.
Eventually, the Enterprise arrived and Maxwell agreed to a meeting with Captain Jean-Luc Picard, explaining that he knew the Cardassians were arming again. The peace treaty was a ruse to give them time to re-group. He had undertaken these unauthorized attacks because he did not trust the "bureaucrats" in Starfleet to take decisive action, an assertion to which Picard responded by stating his opinion that Maxwell was simply seeking revenge for the death of his family. Maxwell was also reunited with O'Brien, who was serving as transporter chief, and the two men greeted each other warmly as old friends. Maxwell also complimented the chief's abilities as a tactical officer. Miles expressed his own admiration for his former Captain.
Subsequent to Picard ordering him to travel to Starbase 211 under escort, Maxwell feigned compliance, but altered course en route, leading the Enterprise-D to another Cardassian supply vessel. Maxwell claimed it was transporting weapons in preparation for an attack on Federation space. Imploring Picard to search the ship in an attempt to prove his assertions, Maxwell threatened to destroy it, along with all hands. He was eventually talked down by O'Brien. Realizing that he had lost, Maxwell willingly surrendered to Picard, turning over command of the Phoenix to his first officer. (TNG: "The Wounded")
"Smells musty in here... like a bureaucrat's office."
- - Maxwell, while in Picard's ready room
"You're a fool, Picard. History will look at you and say: 'This man was a fool.' "
"I'll accept the judgment of history."
- - Captain Maxwell and Captain Picard
"I'm not gonna win this one, am I, Chief?"
- - Benjamin Maxwell and Miles O'Brien, after Maxwell decides to surrender
Captain Benjamin Maxwell was played by actor Bob Gunton.
The script for "The Wounded" describes Maxwell as, "not at all what one might have expected. Slight of build, short greying hair, chiseled, angular face -- he could be Lenin. Or Lennon. But in the eyes there is warmth -- and humor. Creases at the edges testify to a lifetime of smiles and laughter. He is genuinely at ease with himself, and consequently puts others at ease." 
Author and writer Larry Nemecek noted that Maxwell's "Queeg-like turn" echoed Matt Decker from the Star Trek: The Original Series episode "The Doomsday Machine". (Star Trek: The Next Generation Companion (1st ed., p. 152))
The DS9 novel Force and Motion established that, after being incarcerated for nearly two decades, Maxwell was employed as a maintenance engineer on the private science station Robert Hooke. In early 2386, he is reunited with O'Brien when he and Lieutenant Commander Nog travel to the station to meet with the station's owner, Anatoly Finch, who introduces them to a genetically engineered lifeform called "Mother" that Finch claims can neutralize toxins left behind during the Borg attack of 2381. When one of Finch's assistants, Sabih Ali, apparently attempts to steal Mother, triggering a security system that kills him and flushes Mother out into space, Maxwell works out that Sabih was working under Finch's orders as Finch had already arranged to sell Mother to a group of Romulan farmers. When the station suffered a technical failure from Finch's plan and severe damage from Mother being attracted to the warp reactors, O'Brien and Nog arrange for the evacuation of most of the station's personnel, but Maxwell stays behind to repair the warp core and discovers that Mother is sentient and largely peaceful. Maxwell was believed to have died in the station's destruction, but he had actually left in the transport, hoping for a fresh start.