Frederick Braun, M.D., Ph.D., various other Ds, pushed his slightly crooked horn-rims back on his nose and looked up at the two-story wooden house. There was a small lawn before it, moderately cared for, and one tree. There was the usual porch furniture, and the house was going to need painting in another six months or so, but not quite yet. There was a three-year-old hover car parked at the curb of a make that anywhere else in the world but America would have been thought ostentatious in view of the seeming economic status of the householder.

Frederick Braun looked down at the paper in his hand, then up at the house again. He said to his two companions, "By Caesar, I will admit it is the most average-looking dwelling I have ever seen."

Patricia O'Gara said impatiently, "Well, do we or don't we?" Her hair should have been in a pony tail, or bouncing on her shoulders, or at least in the new Etruscan revival style, not drawn back in its efficient bun.

Ross Wooley was unhappy. He scratched his fingers back through his reddish crew cut. "This is going to sound silly."

Patricia said testily, "We've been through all that, Rossie, good heavens."

"Nothing ventured, nothing ..." Braun let the sentence dribble away as he stuffed the paper into a coat pocket, which had obviously been used as a waste receptacle for many a year, and led the way up the cement walk, his younger companions immediately behind.

He put his finger on the doorbell and cocked his head to one side. There was no sound from the depths of the house. Dr. Braun muttered, "Bell out of order."

"It would be," Ross chuckled sourly. "Remember? Average. Here, let me." He rapped briskly on the wooden door jamb. They stood for a moment then he knocked again, louder, saying almost as though hopefully, "Maybe there's nobody home."

"All right, all right, take it easy," a voice growled even as the door opened.

He was somewhere in his thirties, easygoing of face, brownish of hair, bluish of eye and moderately good-looking. His posture wasn't the best and he had a slight tummy but he was a goodish masculine specimen by Mid-Western standards. He stared out at them, defensive now that it was obvious they were strangers. Were they selling something, or in what other manner were they attempting to intrude on his well being? His eyes went from the older man's thin face, to the football hero heft of the younger, then to Patricia O'Gara. His eyes went up and down her figure and became approving in spite of the straight business suit she affected.

He said, "What could I do for you?"

"Mr. Crowley?" Ross said.

"That's right."

"I'm Ross Wooley and my friends are Patricia O'Gara and Dr. Frederick Braun. We'd like to talk to you."

"There's nobody sick here."

Patricia said impatiently, "Of course not. Dr. Braun isn't a practicing medical doctor. We are research biochemists."

"We're scientists," Ross told him, putting it on what he assumed was the man's level. "There's something on which you could help us."

Crowley took his eyes from the girl and scowled at Ross.