It has been shown that a person's mood can influence pain tolerance. Films have been used as a means of inducing a desired mood. The effect on pain perception of film type and film length to induce mood was investigated. Previous research with brief humorous films had not indicated any unique advantage of humor over distraction approaches. Other recent research had indicated that after exposure to film stimulation there is a need to wait approximately 40 min before physiological changes can be obtained. Thus, the present study varied both film type and length and introduced a 30-min waiting period following the mood induction via film prior to exposure to cold-presser pain. Two hundred subjects in nine different groups participated in the study. Three types of films were used: (1) humorous, (2) holocaust, (3) neutral. Three lengths of each type were also used: 15 min. 30 min, and 45 min. In addition, a tenth no-film group served as a control for the effects of a film. Each subject was given a baseline trial of cold-presser pain, a trial immediately following the film and a trial 30 min later. Results indicated an advantage in increased pain tolerance for the humorous film and an increased pain tolerance for the longer film regardless of type only after the 30-min waiting period. Results were discussed from a pain theoretical perspective with emphasis placed on returning to psychological manipulations of the sensory aspects of pain and not just the cognitive/emotional/motivational dimensions. (C) 1998 International Association for the Study of Pain. Published by Elsevier Science B.V.