I used to go round to visit my mum, & she always watched When The Boat Comes In, as she grew up in Tynesid in the era when it was set. I must admit I got hooked on it & it is still my favorite in that type of drama. Considering how popular it was I'm surprised it's not been repeated
Hi Amanda Mc
Do not know the TV series but one of my all-time favourite folk tunes is subtitled "When the Boat Comes In," (we'll have a fishy, in a little dishy etc) which is an English tune picked up by an Irish band, Horslips, for their debut album "Happy to Meet, Sorry to Part." If that is your song, that is the best verison I know of it.
Forgot to mention it, but the song itself must be very old as when ever mum heard it she would comment that one of the first things she could remember was her mum singing it to her.