After being attacked by the Apache when a sound of thunder (actually a crashing spaceship) frighten them away, Breen and Verity continue on to Silver City and discovered that the entire town is rundown and vacated except for Alan Cross, head of the Silver City Homesteaders' Bureau and the town's mayor. Breen shared his confusion to Cross for the town's desolate state given that it was described as a boomtown which he then learns from the latter that Silver City went bust after its silver mine was depleted, in which it occurred six month ago - the exact time when Breen and his people left from Buffalo. Although, Breen was reassure by Cross he had land reserved for his people. Thereafter, Breen and the others were warned by Zeke about the aliens led by Commander Dar, in which Breen had no trouble finding it unbelievable given his avid reading on science fiction. When the aliens attack Silver City, Breen led his people in fleeing from the aliens to a narrow maze of canyon and being rescued by the Apaches led by Chief Medicine Crow.
Breen and his settlers were offer shelter for three days only and quickly learns from Medicine Crow that Cross had swindle the settlers into living on Indian land that was promised to the Apache. In outrage, Breen and the settlers chased after Cross for his deception. Later, Breen was at attendance in hearing Ra Chak Kai's warning about the aliens and their intention in contacting a large spaceship fleet of the House of Dar to conquer Earth by building a beacon at the center of Silver City. Breen participated in the raid on the town as a diversion for Zeke, War Hawk, and Kai to destroy the beacon. However, the raid was repel and Breen was knocked out and imprisoned at the town's jail alongside with Verity and Chief Medicine Crow. He was also witness to Cross's betrayal in attempting to side with Commander Dar, which failed, and saw to his punishment committed by Verity.
By the next morning Breen and the others were sentenced to a firing squad and were fortunately saved by the settlers and Apaches, and ultimately defeating the aliens. In the aftermath, Breen engage with Medicine Crow in establishing a peaceful alliance and coexistence between the settlers and the Apache. .