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"You're going to have to go to work, Paul," said Della Street. "Petty's taken a button ans sewn a vest on it."
"Della's right, Paul," Mason said. "It's like the old phony jewelry store bad-check racket."
"Who's the victim?"
"Otto Olney."
"Not on that painting deal? Drake asked. "Is the painting phony?"
"No, the painting is absolutely genuine. But I have a hunch the witness is going to disappear. If that happens, everyone will know that Perry Mason was played for a sucker."
"Well," Drake said thoughtfully, "it's a damned good vest button and it may fit on a vest. How do we start finding out?"
And Perry's instinct was right. They had set him up for a sucker, but they hadn't allowed for his suspicious nature or for murder!