S1·E17 Down to a Sunless Sea

Vincent has foreboding dreams when Catherine's ex-fiancé Steven Bass returns, and with good reason: Catherine is barely aware Steven—whose parents are now dead and who's dying of brain disease, but whose becalmed manner at first belies that he's still a control freak—is obsessed with making her the wife she doesn't want to be, and goes to troubling extremes to make it happen.