With his white hair and face cracked with wrinkles that bespoke the personification of kindliness and wisdom, Seneca is perhaps best remembered for his critically praised portrayal of a blues singer in "Crossroads" (1986). He spent much of the 1950s as a singer with the satirical group The Three Riffs and most of the 60s as an itinerant composer. From 1970-73, Seneca was a contributing writer for the acclaimed PBS children's show "Sesame Street."