
The Ambushers is a novel by Donald Hamilton first published in 1963, continuing the exploits of assassin Matt Helm.

The Annihilators, published in 1983, was the twentieth novel in the long-running secret agent series Matt Helm by Donald Hamilton.

The Betrayers is the tenth novel in the Matt Helm spy series by Donald Hamilton, which originated with Death of a Citizen in 1960. This novel was first published in 1966. It was reissued in 2014 by Titan Books.

The Damagers, published in 1993, is a spy novel by Donald Hamilton, and the twenty-seventh volume of the adventures of government assassin Matt Helm. Hamilton had launched the series in 1960 with Death of a Citizen and this novel is a sequel to the second Helm book, The Wrecking Crew, also from 1960.

Death of a Citizen is a 1960 spy novel by Donald Hamilton, and was the first in a long-running series of books featuring the adventures of assassin Matt Helm. The title refers to the metaphorical death of peaceful citizen and family man Matt Helm and the rebirth of the deadly and relentless assassin of World War II.

The Demolishers, published in 1987, is a novel in the long-running secret agent series Matt Helm by Donald Hamilton.

The Detonators, published in 1985, is a novel in the long-running secret agent series Matt Helm by Donald Hamilton.

The Devastators is the ninth novel in the Matt Helm spy series by Donald Hamilton. It was first published in 1965.

The Frighteners is a 1989 spy novel by Donald Hamilton, continuing the adventures of his creation, assassin Matt Helm.

The Infiltrators was the twenty-first novel in the spy series Matt Helm by Donald Hamilton. It was first published in 1984.

The Interlopers, first published in 1969, was the twelfth novel in the Matt Helm spy series by Donald Hamilton, which began in 1960. It represents a middle period in the Helm novels, being about 80,000 words in length, somewhat longer than the first four or five in the series, but considerably shorter than most of the Helm books of the eighties and nineties, which were generally well over 100,000 words in length. At this intermediate length, the action moved swiftly while still allowing for plot complications, but avoided the occasional padded-out-by-dialogue tedium of the later books.

The Intimidators was the fifteenth novel in the Matt Helm secret agent novel series by Donald Hamilton. It was first published in 1974.

The Intriguers, first published in 1972, was the fourteenth novel in the Matt Helm spy series by Donald Hamilton.

The Menacers, first published in 1968, was the eleventh novel in the Matt Helm spy series by Donald Hamilton and the first published since the launch of the Matt Helm film series starring Dean Martin.

Murderers' Row is the title of a 1962 spy novel by Donald Hamilton. It was the fifth novel featuring his creation Matt Helm, a Second World War assassin recruited as a counter-agent by a secret American agency. This was the last Matt Helm novel to not use Hamilton's naming convention of The (Verb)-ers. The expression "murderers' row" had been used previously to describe the batting line-up of the New York Yankees baseball team in the late 1920s.

The Poisoners was the first Matt Helm novel of the 1970s. It was first published in 1971, as the thirteenth novel in the spy series by Donald Hamilton.

The Ravagers is a novel by Donald Hamilton that was first published in 1964. It was the eighth novel in his long-running series of adventures featuring secret agent Matt Helm.

The Removers is a spy novel by Donald Hamilton first published in 1961. It was the third novel featuring Hamilton's creation, counter-agent and assassin Matt Helm.

The Retaliators was the seventeenth novel in the Matt Helm secret agent novel series by Donald Hamilton. It was first published in 1976. It was nominated for an Edgar Award in the paperback original category.

The Revengers, published in 1982, is a novel in the long-running secret agent series Matt Helm by Donald Hamilton. It was the first Helm book published since 1977 and the nineteenth book published overall since 1960.

The Shadowers is a novel by Donald Hamilton first published in 1964, continuing the exploits of assassin Matt Helm. It was the seventh novel of the series.

The Silencers is the title of a 1962 spy novel by Donald Hamilton, the fourth in a series of books featuring assassin Matt Helm.

The Terminators by Donald Hamilton is a spy novel first published in April 1975. It was the sixteenth episode in the Matt Helm series and was the first of the Helm books to portray him, on its cover, as a long-haired, side-burned citizen of the 1970s. This image was subsequently used for reprinted editions of a number of the earlier stories.

The Terrorizers was the eighteenth novel in the Matt Helm secret agent novel series by Donald Hamilton. It was first published in 1977. Following the publication of this book, Hamilton put his longtime character on hiatus; the next Matt Helm novel, The Revengers, would not be published until 1982.

The Threateners is the title of a spy novel by Donald Hamilton first published in 1992. It was the twenty-sixth installment of the Matt Helm series, and saw the return of the character after a three-year hiatus.

The Vanishers is the title of a spy novel by Donald Hamilton which was first published in 1986. It is the twenty-third book in a series of novels featuring the adventures of assassin Matt Helm.

The Wrecking Crew is a spy novel written by Donald Hamilton and first published in 1960. It was the second novel featuring Hamilton's ongoing protagonist, counter-agent and assassin Matt Helm. In this book Hamilton continued the hard-headed and gritty realism he had built up around Helm in the first novel of the series, Death of a Citizen.