Complex sentence: When the widowed Jim Flett comes to town to be a school teacher ("The Strap"), Grace has absolutely no interest in him whatsoever, but towards the end of season four, Grace and Jim become an item.
Split into simpler sentences: When the widowed Jim Flett comes to town to be a school teacher (the Strap), Grace has absolutely no interest in him what-so-ever. But, towards the end of season four, Grace and Jim become an item.