Pat almost ran the few blocks to her home. She hastened along in a near panic, regardless of the glances of pedestrians she chanced to pass. With the disappearance of the immediate urge, the composure for which she had struggled had deserted her, and she felt shaken, terrified, and weak. Her arm ached miserably, and her wrenched shoulder pained at each movement. It was not until she attained her own door-step that she paused, panting and quivering, to consider the events of the evening.

"I can't stand any more of this!" she muttered wretchedly to herself. "I'll just have to give up, I guess; I can't pit myself another time against—that thing."

She leaned wearily against the railing of the porch, rubbing her injured arm.

"Dr. Carl was right," she thought. "Nick was right; it's dangerous. There was a moment there at the end when he—or it—almost had me. I'm frightened," she admitted. "Lord only knows what might have happened had I been a little weaker. If the Lord does know," she added.

She found her latch-key and entered the house. Only a dim light burned in the hall; her mother, of course, was at the Club, and the maid and Magda were far away in their chambers on the third floor. She tossed her wrap on a chair, switched on a brighter light, and examined the painful spot on her arm, a red mark already beginning to turn a nasty blue, with two tiny specks of drying blood. She shuddered, and trudged wearily up the stairs to her room.

The empty silence of the house oppressed her. She wanted human companionship—safe, trustworthy, friendly company, anyone to distract her thoughts from the eerie, disturbing direction they were taking. She was still in somewhat of a panic, and suppressed with difficulty a desire to peep fearfully under the bed.

"Coward!" she chided herself. "You knew what to expect."

Suddenly the recollection of her parting words recurred to her. She had told Nick—if Nick had indeed heard—to come to the house, to come at once, tonight, if he could. A tremor of apprehension ran through her. Suppose he came; suppose he came as her own Nick, and she admitted him, and then—or suppose that other came, and managed by some trick to enter, or suppose that unholy fascination of his prevailed on her—she shivered, and brushed her hand distractedly across her eyes.

"I can't stand it!" she moaned. "I'll have to give up, even if it means never seeing Nick again. I'll have to!" She shook her head miserably as if to deny the picture that had risen in her mind of herself and that horror alone in the house.

"I won't stay here!" she decided. She peeped out of the west windows at the Doctor's residence, and felt a surge of relief at the sight of his iron-gray hair framed in the library window below. He was reading; she could see the book on his knees. There was her refuge; she ran hastily down the stairs and out of the door.

With an apprehensive glance along the street she crossed to his door and rang the bell. She waited nervously for his coming, and, with a sudden impulse, pulled her vanity-case from her bag and dabbed a film of powder over the mark on her arm. Then his ponderous footsteps sounded and the door opened.

"Hello," he said genially. "These late evening visits of yours are becoming quite customary—and see if I care!"

"May I come in a while?" asked Pat meekly.

"Have I ever turned you away?" He followed her into the library, pushed a chair forward for her, and dropped quickly into his own with an air of having snatched it from her just in time.

"I didn't want your old arm-chair," she remarked, occupying the other.

"And what's the trouble tonight?" he queried.

"I—well, I was just nervous. I didn't want to stay in the house alone."

"You?" His tone was skeptical. "You were nervous? That hardly sounds reasonable, coming from an independent little spit-fire like you."

"I was, though. I was scared."

"And of what—or whom?"

"Of haunts and devils."

"Oh." He nodded. "I see you've had results from your letter-writing."

"Well, sort of."

"I'm used to your circumlocutions, Pat. Suppose you come directly to the point for once. What happened?"

"Why, I wrote Nick to get in touch with me, and I got a reply. He said to meet him in the park at a place we knew. This evening."

"And you did, of course."

"Yes, but before that, this afternoon, he called up and told me not to, but I insisted and we did."

"Told you not to, eh? And was his warning justified?"

"Yes. Oh, yes! When I came to the place, it was—the other."

"So! Well, he could hardly manhandle you in a public park."

Pat thought of her wrenched shoulder and bruised arm. She shuddered.

"He's horrible!" she said. "Inhuman! He kept referring to Saturday night, and he threatened that if I moved or made a disturbance he'd let Nick suffer the consequences. So I kept still while he insulted me."

"You nit-wit!" There was more than a trace of anger in the Doctor's voice. "I want to see that pup of yours! We'll soon find out what this thing is—a mania or simply lack of a good licking!"

"What it is?" echoed Pat. "Oh—it told me! Dr. Carl, what's a synopsis?"

"A synopsis! You know perfectly well."

"I mean applied to physiology or psychology or something. It—he told me he was a question of synopsis."

"This devil of yours said that?"

"Yes."

"Hum!" The Doctor's voice was musing. He frowned perplexedly, then looked up abruptly. "Was it—did he by any chance say synapses? Not synopsis—synapses?"

"That's it!" exclaimed the girl. "He said he was a question of synapses. Does that explain him? Do you know what he is?"

"Doesn't explain a damn thing!" snapped Horker. "A synapse is a juncture, or the meeting of two nerves. It's why you can develop automatic motions and habits, like playing piano, or dancing. When you form a habit, the synapses of the nerves involved are sort of worn thin, so the nerves themselves are, in a sense, short-circuited. You go through motions without the need of your brain intervening, which is all a habit amounts to. Understand?"

"Not very well," confessed Pat.

"Humph! It doesn't matter anyway. I can't see that it helps to analyze your devil."

"I don't care if it's never analyzed," said Pat with a return of despondency. "Dr. Carl, I can't face that evil thing again. I can't do it, not even if it means never seeing Nick!"

"Sensible," said the Doctor approvingly. "I'd like to have a chance at him, but not enough to keep you in this state of jitters. Although," he added, "a lot of this mystery is the product of your own harum-scarum mind. You can be sure of that, Honey."

"You would say so," responded the girl wearily. "You've never seen that—change. If it's my imagination, then I'm the one that needs your treatments, not Nick."

"It isn't all imagination, most likely," said Horker defensively. "I know these introverted types with their hysterias, megalomanias, and defense mechanisms! They've paraded through my office there for a good many years, Pat; they've provided the lion's share of my practice. But this young psychopathic of yours seems to have it bad—abnormally so, and that's why I'm so interested, apart from helping you, of course."

"I don't care," said Pat apathetically, repressing a desire to rub her injured arm. "I'm through. I'm scared out of the affair. Another week like this last one and I would be one of your patients."

"Best drop it, then," said Horker, eyeing her seriously. "Nothing's worth upsetting yourself like this, Pat."

"Nick's worth it," she murmured. "He's worth it—only I just haven't the strength. I haven't the courage. I can't do it!"

"Never mind, Honey," the Doctor muttered, regarding her with an expression of concern. "You're probably well out of the mess. I know damn well you haven't told me everything about this affair—notably, how you acquired that ugly mark on your arm that's so carefully powdered over. So, all in all, I guess you're well out of it."

"I suppose I am." Her voice was still weary. Suddenly the glare of headlights drew her attention to the window; a car was stopping before her home. "There's Mother," she said. "I'll go on back now, Dr. Carl, and thanks for entertaining a lonesome and depressed lady."

She rose with a casual glance through the window, then halted in frozen astonishment and a trace of terror.

"Oh!" she gasped. The car was the modest coupe of Nicholas Devine.

She peered through the window; the Doctor rose and stared over her shoulder. "I told him to come," she whispered. "I told him to come when he was able. He heard me, he or—the other."

A figure alighted from the vehicle. Even in the dusk she could perceive the exhaustion, the weariness in its movements. She pressed her face to the pane, surveying the form with fascinated intentness. It turned, supporting itself against the car and gazing steadily at her own door. With the movement the radiance of a street-light illuminated its features.

"It's Nick!" she cried with such eagerness that the Doctor was startled. "It's my Nick!"