80s family movie The Last Electric Knight (Kid) on VHS Video tape.
This TV special was a pilot of sorts to the 1986-1987 ABC series "Sidekicks" starring Ernie Reyes, Jr. and Gil Gerard.
The story of Ernie, a young karate champion, who takes care of his ageing, dying grandfather. The grandfather, realising death is near, chooses an unknowing neighbour, Police Sergeant Rizzo, to care for his grandson. Reluctantly accepting his charge, Rizzo discovers that the boy possesses special martial arts powers that are useful in dealing with criminals.