'Risico' (1960) by Ian Fleming

Bond is sent by M to investigate a drug-smuggling operation based in Italy that is sending narcotics to England. M instructs Bond to get in touch with a CIA informant, Kristatos, who in turn tells Bond that a man named Enrico Colombo is behind the racket. When Bond sets out to find more information on Colombo, he is captured and brought aboard Colombo's ship, the Colombina. Colombo informs Bond that Kristatos is actually the one in charge of the drug-smuggling operation, and that Kristatos is backed by the Russians.

Colombo agrees to help Bond by providing information about things "as long as none of it comes back to Italy"; Bond agrees to help Colombo eliminate Kristatos. Bond, Colombo and his men sail the Colombina to Santa Maria, where Kristatos's men are in the process of loading another shipment of drugs. They attack Kristatos's ship and adjacent warehouse and discover Kristatos lurking near the warehouse, preparing to detonate a bomb. Kristatos tries to escape, but is killed by Bond.