In his civilian identity, criminologist Richard Wentworth is convinced that The Octopus is receiving information from the inner circle of business leaders with whom Wentworth and Police commissioner Kirk regularly consult. To test the hypothesis, he has Kirk invite the men to a dinner at which Wentworth will announce new tools and tactics in the war against The Octopus. Once he relates that a demonstration will take place at the airport, the Octopus's man (we don't see his face) rather blatantly punches holes in a dinner role and has a waiter take it away. The roll is conveyed to a driver outside who recognizes the punch patter as a coded signal directing the Octopus gang to the airport -- where the police are waiting for them. Updated by radio, Wentworth informs the diners that the airport has already been attacked, in vain, but neither he nor Kirk noticed the business with the roll. Still, their task becomes much easier now. Kirk can put tails on all the business leaders rather than flail all over town looking for leads.
The Octopus makes another attempt to draw The Spider into the open, spreading a rumor that his top henchman Steve Harmon (Marc Lawrence) has defected and is on the run. As Blinky McQuade, Wentworth learns where Harmon is holed up. As The Spider, he calls Harmon and negotiates a meeting. Mutual distrust realistically prevails, but each man is willing to take a chance on a meeting in the park. Each also hedges his bets. Wentworth plants a dummy Spider on a bench for Harmon to shoot, while Harmon has men in hiding for when the real Spider shows up -- in a tree. The encounter proves inconclusive as Harmon shoots his way free. Harmon's pretty smart for a serial goon but he doesn't use his head after all this to investigate how The Spider got his number.
Meanwhile, Kirk recruits Nita Van Sloan, Wentworth's girlfriend and The Spider's henchwoman, to help shadow the business leaders, since she has innate society connections to their circle. The Octopus strikes preemptively, driving Kirk's car off the road and snatching the dazed commissioner. Nita jumps free before the wreck and witnesses the kidnapping. She hops on the running board of the kidnap vehicle, and that's the last we see of her this chapter.