Della goes on secondment to the rural Carmarthenshire museum in order to oversee its re-opening. Caleb becomes plagued with visions of the past.

Della tries to get a blockbuster for the Museum, Caleb discovers a painting of the legend of the lady of the small lake, which brings up some haunting memories.

Della succeeds in securing the notorious Mold Cape for the Museum, but is worried that Fioled might try to get her hands on it. An art squad detective visits the Museum.

Tensions run high when Annette from art squad continues to ask difficult questions. On the night of the opening, Annette finally arrests her suspect.

With the net closing in on her, Della makes a devastating decision which brings the missing Rembrandt saga to an end once and for all.

The stolen Mold Cape is recovered. But is this the only thing Fioled will take to the grave with her, or are there more secrets to be unearthed?