Hezekiah is a shadow of the man he once was and Sugar Goodson is drinking himself to death. Just as Wapping looks as though it is about to sigh its last breath, Mary Carr bursts back into town with her loyal second, Alice Diamond, in tow. Mary has arrived back to reassemble the Forty Elephants and reclaim her crown. As always, Mary has a plan.
When Thomas risks his safety to save his family's legacy, Hezekiah has to decide whether he'll step in. Sugar also has a difficult decision to make. Mary's safety is under threat from all sides whilst she tries to keep focussed on her plan. Thomas discovers something that could change his family's lives forever.
Sophie and Alice take over heist preparations. Sugar confronts Treacle about his plans for the Blue Coat Boy and promises he'll make things right. At Prince Albert's fight, Hezekiah is approached by a Black American boxer with an interesting proposition. Meanwhile, with Murtagh's men now following her, Mary's life hangs in the balance.
Murtagh's grip on Treacle tightens as Hezekiah steps back into the ring. On the night of the Graften Ball, everything is set for the heist but things don't go to plan. As Mary contemplates her future, Sugar launches a risky attack on Murtagh. Finally ready to leave Wapping, Hezekiah goes to make his peace with Mary. Is this goodbye forever?