it was nearly two hours later before rigby crept cautiously down the steps and emerged by the way in which he had entered the house. the street as before was absolutely deserted; so far as rigby could see he might have been in a city of the dead. despite his disguise and the artistic make-up of his grimy face, an acute spectator would not have failed to notice the agitation of his features. he crept with trembling footsteps to the roadway, and clung to the railings with a swaying air of one who has seen things the tongue refuses to describe. then his natural courage, fanned by the cool air of the evening and the sense of being no longer isolated, returned with virile force to him. mechanically he fumbled in his rags and produced from a breast pocket a silver cigarette-case, that might have got him into serious trouble if a lynx-eyed policeman had been near at hand.

"well, i have seen some queer things in my time, but, as the poet says, 'never aught like this,'" rigby said, with teeth that chattered a little. "i really must have one of my own cigarettes."

despite his excitement, rigby was conscious that he ought to be just a little ashamed of himself. he had always prided himself upon the fact that his nerves were perfectly under control and that nothing ever put him out, otherwise he would not have occupied the position he did at the planet office. he began to feel the effect of the cool night air, which braced him like a tonic. as he stood there waiting for something--though he would have found it difficult to say what--a policeman came slowly down the street. rigby stooped and pretended to be busy with his stock of papers.

some spirit of mischief moved him to chaff the representative of the law, and at the same time test to the utmost the disguise that he was wearing.

"paper, sir?" he asked. "all the winners--horrible murder in grosvenor square. ain't you going to buy one?"

apparently the officer was one of the good-tempered sort, for he only smiled, and in a more or less gruff voice ordered the news-vender to move on.

"just waiting for my pal, sir," rigby explained. "i have never come down this street before, an' i'll take good care never to come down here again. why, half these houses seem to be empty. look at that show opposite. 'ow long since anybody has lived there?"

"before i came on the beat, anyway," the policeman explained. "do you want to take one?"

with a laugh at his own pleasantry the policeman stalked off down the street, leaving rigby easier in his mind and quite satisfied that his disguise would stand any ordinary test.

he leaned against the area railings absolutely undecided as to what to do next. with a certain new caution almost amounting to cowardice--a feeling of which he would be ashamed at any other time--rigby turned his back upon the man who was advancing down the street. at the same time, so full was he of the horrors that he had lately witnessed, the amateur detective quite forgot the fragrant cigarette so out of keeping with his character. the stranger pulled up and, crossing the pavement, tapped rigby familiarly on the shoulder.

"you are not so clever as you think you are," the stranger remarked coolly. "you may be a very smart chap, dick, and i may be a very dull one, but i have certainly sufficient brains to know that the average newspaper tout does not smoke turkish cigarettes. besides, after our conversation this morning, i felt pretty certain that you would make an attempt to get inside that house."

rigby laughed in a way that suggested that his nerves were in a considerably frayed condition.

"so that's you, jack," he said, with a sigh of relief. "yes, you are quite right; in fact, i told you i should not rest to-night until i had seen the inside of that house."

"and did the expedition come up to expectations?" masefield asked eagerly.

"my dear fellow, i have had some weird experiences in my time, but i would not go through the last hour again for the wealth of the indies. in fact, if i tell you what i've seen, you would set me down for a doddering lunatic."

the look of self-satisfaction on jack's face faded away. he shivered with a strange weird feeling, that strange presentiment of something dire about to happen. again, why should he doubt the fact that something terribly out of the common had happened to rigby after his own amazing experiences?

with his hand on the arm of his friend, he walked abstractedly the whole of the terrace. here a great arc light threw a stream of pallid blue upon the motley coloring displayed upon a big hoarding. in the centre of the hoarding, well displayed, was the terrible placard disclosing the grinning features of nostalgo.

"by heaven!" jack exclaimed, "there is no getting away from the features of that grinning devil. i know as well as if i had seen it down in black and white that the awful experiences which have so changed you lately have to do with that yellow face."

"i am not going to deny it," rigby replied; "and, what is more, i am not going to tell you what i have seen in the last two hours--at least, not at present. and now tell me, to change the subject, what is your private opinion of spencer anstruther?"

to say that jack was taken aback by the suddenness of the question would be a mistake. it will be remembered that on the occasion masefield last dined with anstruther he had pointed out to claire the amazing likeness between nostalgo and her guardian. not that it was possible for anybody to notice this except when anstruther was moved to great emotion; but the fact remained. and now to find that rigby's mind was so strangely moved in the same train of thought was, to say the least of it, disturbing.

"what do you mean by asking that question?" jack said guardedly.

"for goodness' sake do not let us have any of this unnecessary caution between friends like ourselves," rigby said, with great feeling. "believe me, my dear friend, i am not asking this question out of idle curiosity. as man to man, is he a magnificent genius or the greatest criminal the world has ever seen?"

thus put to it, jack had no hesitation; indeed, he could have had no hesitation in replying to such a direct question as this.

"i am going to speak quite candidly to you," he said. "as you are perfectly well aware, knowing the man quite as well as i do, he is, like most geniuses, an exceedingly poor man. at the same time, unlike most geniuses, he is as unscrupulous as he is clever. i have more than an idea that he could tell us all about this affair, but i prefer to pose as a person who has come into it by accident, and who is only languidly interested. i have had some hesitation in mentioning my estimate of anstruther's character to his ward, but i feel very uneasy so far as claire is concerned. i know for a fact that anstruther is painfully hard up; really, there are times when his financial straits are absolutely desperate. this being so, it has occurred to me more than once that claire's money must be a strong inducement to prevent her marrying, for instance, myself."

"that is by no means a remote contingency," rigby suggested drily.

"my dear fellow, to be perfectly frank with you, miss helmsley and myself have been engaged for the past two years. mind you, this is a dead secret. i have a presentiment, call it foolish if you like, that the announcement of this fact to anstruther will be the first moment of real danger for claire. but why do you so suddenly spring this question upon me?"

by way of reply rigby drew his companion into the comparative shadow of a doorway. he had hardly done so before another figure came jauntily down the street--a tall, slim figure which seemed strangely familiar to masefield.

"the whole place seems to reek of anstruther to-night," jack said, "or perhaps it is my disordered imagination. but if that is not anstruther himself, my eyesight strangely deceives me."

"if you knew as much as i do, or you had learned what i have learned the last hour, you would not be surprised," rigby said. "however, we will soon settle that. i'll just step across the road and try and sell him a paper." before jack could lay a detaining hand on the arm of his friend, rigby was half way across the street. in the approved raucous voice of the tribe, the amateur news-vender tendered anstruther an echo. he waved the offer aside, and made his way down the street with the air of one who has a definite object in view. with a whine artistically uttered, rigby fell back upon the doorway in which masefield was concealed.

"anstruther beyond all shadow of doubt," rigby said triumphantly. "now, i am not a betting man, but i will lay you any odds in reason that our interesting friend enters no. 4. ah, what did i tell you?"

surely enough, anstruther paused in his stride before the dilapidated door of no. 4. with one swift glance up and down the street to make certain that he was not observed, he drew a latch-key from his pocket and disappeared within the dingy portals. on the still night air the click of the latch-key and the muffled banging of the door could be heard all down the road. rigby drew a sigh of relief.

"well, i think that'll do for to-night," he said. "i reckon i have had just about as much as my nerves will stand. no, i am not going to tell you anything, and i have no stomach for further adventures this evening. i am going straight to bed, to sleep if i can. come around and see me to-morrow afternoon."

but curious as he was, and anxious also as he was, jack was forced to decline the proffered invitation. besides, he had promised to take claire to a matinee concert at the albert hall, to hear a new violinist who so far had only performed twice before in england. signor padini had come to the metropolis with a marvelous reputation, but so far he had hardly fulfilled expectations. still, it was not the habit of music-lovers like claire and masefield to accept a verdict of this kind at second-hand. therefore they had determined to hear the new virtuoso for themselves.

not that any thoughts of a harmonious and musical kind were running in jack's mind as he walked home to-night. try as he would, he could not dismiss the idea that some grave peril was impending, and that claire was likely to be the central figure of the tragedy. but it is the blessed privilege of youth to throw off the haunting cares and doubts that assail their elders, and jack suffered little on the ground of sleeplessness that night.

all the same, the haunting fears were with him again on waking in the morning.

but perhaps claire noticed something of this, for she put the direct question to her lover when he called on her the next afternoon. yet jack had no intention of saying anything for the present. he began to speak somewhat hurriedly of the new violinist, signor padini, and so the conversation lasted till the albert hall was reached.

there was nothing particularly attractive in the concert generally, and both waited somewhat impatiently for the foreigner to appear. he came at length, tall, slim, and clean-shaven, and claire noticed with an amused smile that for once she was in the presence of a master who eschewed long hair. she turned and whispered something to this effect to jack, who did not appear to be listening.

"now, where have i seen that fellow before?" he muttered. "call me foolish if you like, say this man is an absolute stranger to england if you please; but i am absolutely prepared to swear that his face is quite familiar to me."

but perhaps it was merely a chance likeness, claire suggested. she was far too interested in the musician to take much heed of what jack said. evidently this man knew his business to his finger-tips; the way in which he handled his bow would have proved that to any critic. claire glanced down the programme; and no sooner did the wild sweeping music come streaming from the strings than the whole audience thrilled responsive to the master's touch. he was not, after all, playing the piece standing against his name on the programme, but the peculiar weird and mournful rhapsodie of chopin's that jack had heard anstruther interpreting two nights before. he leaned back; his eyes were half closed with a strange sensation that he was listening to anstruther now. he turned to suggest something of this to claire, and to his surprise he noticed that her face was paler than his own.

"does anything strike you?" he whispered. "have you a feeling, like myself, of having gone through all this before?"

"dreadful!" claire shuddered. "i know exactly what you mean. it is the same, precisely the same, as if my guardian had crept inside the body of padini---- there! did you notice that particular slur, that strange half hesitation? i declare, i feel certain that this padini was in my guardian's study the other night. jack, you must get at the bottom of this; there is some mystery here which we must solve, and that without delay."

jack rose from his seat and buttoned his coat firmly about him.

"ay," he said, "a deeper mystery than you are aware of. stay here while i go behind the stage. i am going to see signor padini, and get to the bottom of this business at any cost."