Colby was an especially prolific writer in the period of 1959 through 1961, when twelve of his seventeen novels were published.
The Quaking Widow (1956)
The Captain Must Die (1959)
The Deadly Desire (1959)
Make Mine Vengeance (1959)
Murder Mistress (1959)
Secret of the Second Door (1959)
These Lonely, These Dead (1959)
The Star Trap (1960)
In a Vanishing Room ( 1961)
Kill Me a Fortune (1961)
Lament for Julie (1961)
Kim (1962)
Beautiful But Bad (1962)
The Faster She Runs (1963)
Executive Wife (1964)
Murder Times Five (1972)
Run for the Money (1973)
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