CHELLAK: Where? DOCTOR (on monitor): And you are? MORGUS: The gun runners. PERI: End of trail. Too small for interstellar travel, so it obviously came from the twin planet of Androzani Major.
Plan: A: The Doctor; Q: Who is mistaken for a gun runner and sentenced to death? A: Androzani; Q: What is the name of the twin planets that the Doctor lands on? A: gun runners; Q: What are the Doctor and Peri mistaken for? Summary: The Doctor lands on one of the twin planets of Androzani where he along with Peri are mistaken for gun runners and sentenced to death.