A new threat challenges ship protocol; Mel notices changes in the crew; Lommie returns to Greywing.

Cast: Eoin Macken, David Ajala, Jodie Turner-Smith, Angus Sampson, Sam Strike, Maya Eshet, Brían F. O'Byrne, Gretchen Mol, Miranda Raison, Phillip Rhys, Gwynne McElveen