"Hullo!" replied the man, noting suspiciously the dress of his fare, "wot's yer little game?" "Police business worth half a sovereign," was Darrel's diplomatic reply. "Blimme, that's all right, sir," said the driver, accepting this explanation with alacrity. "Jump in, an' I'll ketch up t'other keb in two shakes!" Confident that the driver would earn his money, Darrel lay back on the cushions, and wondered what would be the outcome of his pursuit. That the red-headed man should have turned away at the very goal towards which he had requested guidance was most extraordinary. If he had no special business in Mortality-lane, why had he inquired for it? and if he had a reason for going, and his reason was an innocent one, why did he not ask the policeman in Drury-lane instead of applying to a complete stranger? Frank, ever on the alert for romance, asked himself these questions, but could find no answer to them. However, he hoped to gratify his curiosity when he caught up with the stranger who was the cause of it--provided the stranger was willing to afford an explanation. The cab--presumably following the other vehicle--drove down Bell-street, and turned into the Strand, now almost emptied of traffic. It rolled along the thoroughfare as far as Trafalgar-square, then turned down Northumberland-avenue, passed along the Embankment, and up Arundel-street into the Strand again. Darrel was greatly puzzled by this circular route--the more so when he found his cab driving up Drury-lane. Then a sudden thought struck him. "The red-headed man fancied I was watching him," he said to himself, "and drove away to get rid of me. I should not be surprised if the first cab, with him inside, returns to the entrance to Mortality-lane." This proved to be the case, for following almost the same route as he had conducted the stranger, the first four-wheeler drove into the little square and took up its old station at the mouth of the lane. But by this time the third cab left behind had disappeared. "'Ere y'are, sir!" said Darrel's driver, opening the door. "We've both come back 'ome an' never stopped the whole bloomin' time. Carn't mek out wot 'Enry's fare's bin arter." Frank, as puzzled as the cabman, jumped out, and, walking to the first vehicle, looked inside. To his surprise, the red-headed man had vanished. "Wot's wrong with moy keb, mister," said the gruff voice of the driver. "The man--the man with the red hair?" inquired the amazed Darrel. "Oh, 'e's all right. Don't y' fret yerself about 'im. Wot y' poll-pryin' 'ere for, eh?" "Y'd best taike care, 'Enry," remarked the other cabman, sauntering up. "This gent's to do with the perlice." The insolence of Henry gave place at once to respect. "Didn't know you was a 'tec, sir. Might the cove with carrots be wanted?" "He might be," said Darrel, not thinking it wise to disclaim the profession attributed to him by the two cabmen. "When did he get out?" "Well, y' see, sir, he were never in, so to speak."