December in movie history - Assignment to Kill (1968):

Assignment to Kill

directed and written by Sheldon Reynolds,

was released in the United States in December, 1968.
Exact release date unknown.
Music by William Lava.

Cast:

Patrick O'Neal, Joan Hackett, John Gielgud, Herbert Lom, Eric Portman, Peter van Eyck, Oskar Homolka, Leon Greene, Kent Smith, Philip Ober, Fifi D'Orsay, Éva Szörényi, Cynthia O'Neal, Betty Bresler, Karl Bruck, Albert D'Arno, Walter Friedel, Walter Janovitz, Joanne Ludden, Martin Miller, Ann Prentiss, Charles H. Radilak, Erik Sorenson.