YOUNG MAN: Isaac, he said he was a doctor... an alien doctor. DOCTOR: What was that outside? ISSAC: Listen to him. JEX: I am a scientist. A war hero. DOCTOR: The Gunslinger is a cyborg. The DOCTOR walks back into town, but stops and grabs the gun out of a man's holster and aims it at JEX'S head as the doctor tries to cross back into the town. DOCTOR: Jex HAS to answer for his crimes. JEX is "escorted" away and the DOCTOR faces the GUNSLINGER. Help me to... GUNSLINGER: Jex...? COMPUTER: Countdown to self-destruct resumed. The TARDIS is now in the middle of the street. 'By the time the Gunslinger arrived, the people of Mercy were used to the strange and the impossible.
Plan: A: The TARDIS; Q: What accidentally lands in Mercy? A: the American West; Q: Where is Mercy located? A: The TARDIS crew; Q: Who discovers the town's doctor is an alien? A: the cyborg Gunslinger; Q: Who is seeking the town's doctor? A: The Doctor; Q: Who saves the Gunslinger from self-destruction? A: a scientist; Q: What was Jex's profession? A: his home planet; Q: Where did Jex experiment on volunteers to create cyborgs to fight in a war? A: the Gunslinger; Q: Who is seeking revenge for what was done to him? A: a moral dilemma; Q: What does the Doctor face when deciding whether to offer Jex to the Gunslinger? A: a plan; Q: What does the Doctor devise to help Jex escape? A: suicide; Q: What did Jex commit to save innocent people? Summary: The TARDIS accidentally lands in Mercy, a town in the American West around 1870. The TARDIS crew discovers the town's doctor, Jex, is an alien who is being sought by the cyborg Gunslinger. The Doctor discovers Jex was a scientist who experimented on volunteers to create cyborgs to fight in a war on his home planet; the Gunslinger is seeking revenge for what was done to him. The Doctor faces a moral dilemma of whether he should offer Jex to the Gunslinger; he devises a plan to help Jex escape, but Jex commits suicide to save more innocent people from being harmed. The Doctor saves the Gunslinger from self-destruction and makes him the marshal of Mercy.