Season 1 ITV1 , 1978 Watch now Season 2 ITV1 , 1979 - 1980 Watch now Season 3 ITV1 , 1983 Watch now Season 4 ITV1 , 1987 Watch now Season 5 ITV1 , 1988 Watch now Season 6 ITV1 , 1991 Watch now Season 7 ITV1 , 1992 Watch now