The day Mo is due to hand William back to his father arrives, and despite losing her position as the youngster's chief care-giver, she seems remarkably upbeat. However, when Brett faces a sudden medical setback, the cracks begin to show in Mo's ambivalence, and she decides cannot possibly part with her surrogate son. Meanwhile, Sacha is perturbed when Patsy Brassvine, one of the interviewers assessing him for the position of consultant, interferes with his care of a patient, and Serena's mind is diverted from her ex-husband's forthcoming wedding as she tends to a fellow doctor who has been admitted with a toy soldier wedged in his arm.