Cara is feeling vulnerable after the break-up of her marriage as a car crash brings Mo's friend Sorcha and her surrogate son back to Holby.
Cara finds herself in a difficult position when Nicole is readmitted to the ward and in labour as Guy tries to cope following the explosion.
Cara faces awkward questions following Nicole's disappearance and turns to Jed to help as Mo faces giving William back to Brett.
It is Arthur's first day back at work as he tries to prove that he can cope as Guy's struggle of confidence continues to affect his work.
Mo heads into work, positively upbeat considering that she will no longer be surrogate mum to William as she is due to give him back to his father. When Brett faces a sudden medical setback and his mother-in-law Viv becomes obstructive, Mo feels she cannot possibly part with her beloved William and decides to abscond with him...
Nicole's return to AAU makes life more difficult for Cara as Dom's delight at being given a difficult case turns bad when dealing with a difficult patient.
Jac returns to work on Darwin leading to a battle with Guy over his plans as Morven and Arthur end up clashing over a patient.
Zosia fears that her days on Darwin may be numbered as she tries to impress Jac as Arthur tries to rekindle his friendship with Morven.
Jesse has no choice but to relive some tragic events as he attempts to help the seriously ill sister of a former patient.
Fran steps up her manoeuvres against Jac and after she raises the possibility of a formal complaint from a patient's sister, Hanssen has to take it seriously.
Fran returns to the hospital and takes some drastic action to try and get Jac's attention.
It looks like Serena is going to spend another New Year's Eve alone but after some revellers at a gig are attacked, fate brings more than just a few casualties onto the hospital.
Arthur ends up being pushed to the limit after he attempts to win Morven's affections. Zosia has the chance of a prestigious research internship in Edinburgh and has to tell Ollie.
Guy's career continues to go from strength to strength but there is a cost. Essie lets her personal life affect her professional one as she attempts to deal with a difficult mother and son relationship.
Hanssen gets ready to fly back to Sweden to see his family and becomes suspicious that Guy is attempting to wrest control of the hospital something which Guy later publicly announces. Serena looks for reassurance that Hanssen will stay and fight the battle.
Back on Keller, Arthur finds himself in a compromising situation by Morven's father as Mo awaits the news if she is pregnant or not.
After an army medic shows up on Darwin Ward, tensions increase for Guy and Ollie. Serena has to make a difficult decision following the discovery of a family secret.
Somebody from from Dominic's past makes an unwelcome return and there are some traumatic consequences.
Cleared by the police, Dom returns to work but Lee still has the power he needs to hurt him as Austin's condition continues to deteriorate.
Bernie starts her first day on the ward trying to put her army life behind her as Arthur's dream of becoming a life donor gets a set back as Serena has to make a decision regarding Jason.