Grady implicates himself further as a possible suspect in Sandra's death when he does a "favor" for Gary by retrieving an engraved bracelet Gary had given Sandra that Gary claimed was in her bathrobe, and would have made his wife Cornelia jealous if found and publicized. Grady is caught and Jessica has to work double duty to bail him out. One mystery in the murder is that the envelope bearing the phone number Sandra jotted down was never found amongst her belongings. In Jessica's investigating, she discovers that Cornelia and Gary were never actually married, as Gary was married to Sandra, who refused to give him a divorce and was blackmailing him.
Grady overhears Gary bribing an acquaintance to put the heat on him, and finally cuts ties with his old "pal." When Jessica and Grady are about to leave their room for dinner, a fresh carnation on the night maid's tray jogs Jessica's mind to recall that Mark Havlin, the hotel manager, had a fresh carnation in his pocket the night of Sandra's murder. His motive in killing her was that he was on to the fact that she was blackmailing Grady, and wanted a share of the profits. When she didn't agree to it, he did her in. Jessica proves his involvement by feigning ignorance about Sandra's marriage to Grady, and having Havlin produce the marriage certificate from a safe. Written on the back of the envelope is the telephone number Grady had seen Sandra jot down the night she died, exposing it as the one the killer must have taken.
In the closing scene, Gary tells Jessica and Grady that he and Cornelia are getting married "for real" this time, and Gary invites Grady to be his best man. Grady asserts himself by refusing, and Jessica jabs the unwitting couple by saying that she "can't imagine two people more ideally suited."