question:  Why does Pembrook shoot the man in the corner?
context: THE PERFECTIONISTS By ARNOLD CASTLE ILLUSTRATED by SUMMERS Is there something wrong with you? Therefore, it was with a mingled sense of excitement and satisfaction that he greeted the tall, dark, smooth-faced figure that came up the stairs and into the office shortly before noon. Opening the desk drawer, which was almost empty, Pembroke removed an automatic pistol fitted with a silencer. Pointing it at the amazed customer, he fired four .22 caliber longs into the narrow chest. The series of events leading up to Pembroke's present occupation had commenced on a dismal, overcast evening in the South Pacific a year earlier. Standing on the forward deck, Pembroke was one of the first to perceive the peculiar odor and to spot the immense gray hulk wallowing in the murky distance. Then the explosion had come, from far below the waterline, and the decks were awash with frantic crewmen, officers, and the handful of passengers. Only two lifeboats were launched before the Elena Mia went down. Lacking such loyalties, Pembroke adapted quickly to the situation in which he found himself when he regained consciousness. The wallet in his pocket contained exactly what it should, approximately three hundred dollars. One in particular, an attractive woman of about thirty, tossed back her long, chestnut locks and gazed up intently at Pembroke as he passed. "You're not casual enough, for one thing," said Pembroke, deciding to play along with her for the moment. Pembroke watched with lifted eyebrows as the clerk whisked the bizarre statuette underneath the counter. "Incidentally, just where are we, anyway? But as he left the shop he began checking off every west coast state, city, town, and inlet. "Which way is it to San Francisco?" asked Pembroke. Pembroke watched him hurry off to service a car with a sense of having been given the runaround. "Perfect," Pembroke told him. "All cargo ships, I'll bet. No passengers," said Pembroke.
output:  The man in the corner is an android sent by alien masters to facilitate an invasion of Earth.
options:  The man in the corner is one of the strangers.  The man in the corner is an android sent by alien masters to facilitate an invasion of Earth.  The man in the corner was an alien invader.  The man in the corner came to kill Pembrook.