Mo's surrogate son, William, and Sorcia arrive at Holby after an accident, testing Mo's emotional and professional abilities. Jesse shadows Sacha in a surgical role for the day.

Cara's husband's lover, Nicole, is admitted in labour, but Cara is forced to act drastically when Nicole's husband, Sean, learns he is not the father of the child.

Cara's lies put Raf's life in danger as gangster Sean returns to Holby in search of Nicole.

Arthur returns to work, but his relationship with Morven is in jeopardy. Guy must overcome his lack of confidence when a young boy is admitted with a serious neurological condition.

The day arrives for Mo to return William, but she isn't prepared to let him go. Arthur is admitted with a toy soldier stuck in his arm. Sacha applies for the role of consultant, but his assessor intervenes with his treatment options.

Dom deals with a challenging patient who tests his emotional abilities. Nicole asks Cara for help whilst on the run from Sean.

Jac Naylor returns to Darwin, but Ollie is determined to not be intimidated by her. Dom begins to develop feelings for his patient.

Zosia is determined to impress Jac, but her confidence is thrown into doubt when she sees a question mark next to her name in Jac's office. Dom becomes increasingly obsessed in his patient, and struggles to focus on another patient of his.

Jac and Fran clash over a patient when Fran doubts Jac's decision to discharge a patient. Jesse treats a dying sister of a former patient of his. Rad and Fletch try to cheer Cara up.

Jac and Fran bitterly clash in front of the Darwin ward, resulting in Fran physically assaulting Jac and being removed from the hospital.

Jac's daughter, Emma, is abducted by Fran as she attempts to get Jac's attention, however the consequences of Fran's actions are near fatal.

Ric returns to Holby City, but he struggles to find his feet. Mr T makes an unexpected offer to Mo. Serena finds herself completing another Christmas shift on AAU.

Morven, Arthur and Dom battle it out for a research grant, but Morven receives a shock. Jac plays games with Ollie and Zosia's relationship.

Guy's career continues to strengthen and a documentary crew prepare to film him in the neurological world, but he puts a friend's life at risk in the process.

Hanssen is left with a difficult decision as Guy promises to regain control of the hospital. Jac is pitted against Guy in a fight for funding. Sacha tries to protect Essie, but things don't go to plan.

Arthur's first day back on Keller doesn't go smoothly when Morven's dad, Austin, is admitted. Mo waits to find out if she is pregnant. A shock family secret is revealed to Serena.

Bernie Wolfe, an army medic, is admitted to Holby, forcing Guy and Ollie to work together to treat her. Serena has to make a big decision over her family secret revelation.

Dominic finds himself in danger when his ex turns up, and there's traumatic consequences. Zosia becomes over-involved with Bernie's army life. Serena gets a surprise.

Dom is cleared by the police following his incident, however he is still under investigation by the hospital. Morven makes a decision about her own health when Austin's liver disease progresses.

Arthur receives life-changing news as he takes compatibility tests to give Austin a new liver. Bernie is back on her feet and works on Darwin for the day, but she ends up breaking the rules.

Arthur struggles to come to terms with his recent diagnosis and tries to forget it by fighting for the life of a patient hit by a train.

Ric fights for an old friend's life. Serena is in love with Robbie, and prepares to introduce him to her family. Mo learns she didn't get the consultant position.

Bernie has to re-evaluate doctoring when a patient makes a formal complaint against her. Ollie fights to save his relationship with Zosia.