In the meantime, Duke was to pacify Gething by promising him a full explanation of the apparent discrepancies, together with a sight of the actual cash needed to put matters right, on the receipt of certain letters from America. He was also to get together as large a collection of stones as he possibly could. He was then to ask Gething to meet him at the office on the evening in question—the evening of the day of Miss Winter’s first interview with Williams—to go into the whole matter and see the proofs that all was right. Having thus got Gething into his power, he was to murder him, take out the diamonds and some money that was also in the safe, and having handed over to Miss Winter the few stones for Williams, go home as quickly as possible with the remainder. Though this scheme seemed to them good, the conspirators were not satisfied with it, and they added on three additional features to safeguard themselves still further in the event of suspicion being aroused. The first of these was an alibi for Mr. Duke. He arranged that he would dine and spend the evening at his club with his solicitor, leaving at a certain definite prearranged hour. By suitable remarks to the solicitor and the club porters, he would fix this hour, and by similar remarks to his servants he would establish the time at which he reached his house. The interval between would be sufficient to enable him to walk home, and he would take care to inform the police that he had so occupied it. But in reality he would taxi from near the club to near the office, commit the murder, and return to Hampstead by tube. The second safeguard took the form of an attempt to throw suspicion on to Vanderkemp. In carrying this out, Duke himself typed the secret instructions which brought the traveller to London, and he gave Gething orders to see Vanderkemp on his arrival, send him on his wild goose chase to the Continent, and hand him some of the notes of which he had reason to believe the bank had the numbers, and which he afterwards swore were stolen from the safe.