It only took Jimmy Valentine one week to be back in the safecracking business after he was released from prison and had retrieved his set of specialized tools. The tools are mentioned frequently throughout the narrative because they will be used to open the new burglar-proof bank vault in Elmore to release the little girl trapped inside. They will also be evidence against him if Ben Price arrests him after he releases the little girl. It can be shown incontrovertibly that Jimmy's tools were the ones used for three bank jobs. Here is the main evidence in the story, slightly abridged, that Jimmy is back to safecracking.
A week after the release of Valentine, 9762, there was a neat job of safe-burglary done in Richmond, Indiana, with no clue to the author....Two weeks after that a patented, improved, burglar-proof safe in Logansport was opened like a cheese to the tune of fifteen hundred dollars, currency; securities and silver untouched....Then an old-fashioned bank-safe in Jefferson City became active and threw out of its crater an eruption of bank-notes amounting to five thousand dollars....Ben Price investigated the scenes of the robberies, and was heard to remark: “That's Dandy Jim Valentine's autograph. He'll do his bit next time without any short-time or clemency foolishness.”
Ben Price is prepared to arrest Jimmy even before he catches him red-handed in the Elmore bank with all his state-of-the art tools. Price already believes that Jimmy was the perpetrator of the three banks jobs described in the text without having the tools as evidence. The damage to those three safes can be compared with the damage done in previous jobs for which Jimmy was arrested and convicted. As Price says, "That's Dandy Jim Valentine's autograph." Jimmy is getting too well known. He is too good at his craft. He is beginning to realize this himself. It is one of the reasons he wants to reform. But Ben Price had no idea that when he went to arrest Jimmy he would actually catch him opening a safe inside a bank and that he could seize all of Jimmy's tools to use as further evidence against him. Jimmy would have had to spend many years in prison if Price had not seen how he sacrificed everything in order to save that little girl. That proved to the detective that Jimmy was a reformed man and no longer a danger to banks or society.