Independent filmmaker Rob Nilsson's Signal 7 is dedicated to John Cassavetes, who pioneered the extensive use of improvisation in his movies. This gritty drama centers around a day in the life of two middle-aged San Francisco cab drivers. Marty (Dan Leegant) is a cynical and sarcastic fellow who likes to be center stage at the DeSoto cab garage gatherings with other drivers. His buddy Speed (Bill Ackridge) is undergoing a mid-life crisis which has affected his marriage.

One of the strengths of Signal 7 is the way in which the film presents men relating to other men. Although they tell stories and jokes and discuss the need for a union, these individuals find it difficult to share their true feelings. A driver is shot, and the mourning process turns into a brawl. Another cabbie's dreams of seeing up a business selling starch pills is put down by the others in the group.

In the last two sequences in the film, Marty and Speed open up, but not to each other. Hearing about the pain a black driver is undergoing at home over the breakup of his family, Marty retells the true story of a "sex bang" encounter with a husband and wife. He then reveals the depth of his loneliness and the guilt he feels over leaving his wife and child in Korea.

Speed, after auditioning for a theatrical production of Clifford Odet's 1930s play Waiting for Lefty, goes home and does an exercise suggested by the director in which he imagines himself to be an egg. The exercise results in an epiphany — Speed sees himself as a phony. Laughing, crying, he reveals his inward pain abut the failure of his life to his wife. Signal 7 speaks volumes about the anger, loneliness, and anguish of men alone and in groups.