Silliphant was known for his involvement in two TV series of the sixties, "Route 66" and "Naked City". Silliphant was quoted as saying that a number of his "Naked City" scripts were far superior to the script that won him the Oscar for "In the Heat of the Night". He adapted eight half-hour episodes of "Naked City" into a tie-in paperback as well, which was published in 1959. One of his later series creations was "Longstreet", which featured a blind detective played by James Franciscus, who had also starred in the first season of "Naked City".