Flash floods throw Holby City hospital into chaos when the wards are inundated with patients, leaving the staff over-stretched and under pressure. Nobody feels the pressure more than nurse Donna Jackson whose mind is preoccupied with the interview for the job of ward sister. The new role would provide Donna with a much needed pay rise, allowing her to take proper care of her half-niece Mia, whom she’s planning to adopt. After a disastrous interview, Donna is despondent to learn that her best mate Maria has won the job. The two find themselves with scores to settle when they become stuck in a lift together, but it's not long before a greater crisis arises. Having left Mia in the hands of the hospital crèche, a potentially devastating situation occurs when the toddler goes missing. Knowing that a suspected paedophile is being treated in the hospital and also missing, the race is on to bring Mia back to safety. Elsewhere; the floods cause a crisis when the electrical generators fail during Connie performing heart surgery on friend Elaine. Mark squares up to Davina – his rival for the job of CEO.
