Two children go missing and suspicion falls on a local convicted paedophile, while Abs is still reeling from Simon's death.
Comfort discovers she's pregnant and plans a romantic dinner for Fin, but his ambulance is involved in an accident while attending a bogus call.
A worried Comfort calls the police when she realises Fin has not been home and no one at work has heard from him. Luke turns up at Kate's house to check if she's all right.
Concern mounts over Fin's disappearance and a new lead prompts police to step up their search. Luke persuades Kate to seek refuge with him.
Comfort is asked to identify a body, and desperately hopes it will not be Fin, while Abs is startled when Ellen makes him a proposition.
Fin's ex-wife and son turn up at the funeral, reopening fresh wounds for Comfort, who collapses during the burial and is taken to hospital with stomach pains.
Comfort discharges herself from hospital, determined to keep her pregnancy secret, but on returning to work her world is rocked by a shocking revelation.
Comfort comes face-to-face with Fin's killer, who asks for her forgiveness as he stands on the brink of suicide, while Ellen announces she is marrying Abs.
A confrontation with Ruth brings further pain for Comfort, Selena is reprimanded for not doing a thorough examination and Abs tells Claire the real reason he's marrying Ellen.
Comfort arrives home from the Christmas party to find Ruth has changed the locks on the door, Selena harasses Bex relentlessly throughout the day and Abs reprimands Sam.
The casts of Casualty and Holby City unite. The emergency and surgical staff are thrown together when a fuel tanker crashes into the hospital.
Harry tries to raise morale on the ward following Jim's death, Ellen receives unwelcome news about her visa and Bex struggles to deal with Selena's bullying.
Boy-band McFly visit an injured fan after she falls from a window-cleaner's cradle, and Ellen's worries mount over her return to Ukraine.
Comfort is rushed to Holby with stomach pains following a strenuous job, and Abs is in for a shock when he comes face to face with Ellen's father.
Abs continues to give Nina the cold shoulder and loses his cool when Ellen tries to worm her way back into his good books. Meanwhile, Bex thinks she has found the one.
Abs gives Ellen her marching orders when he catches her lying again. Tess grows concerned about Sam's strange behaviour and new registrar Maggie finds duty calls.
Abs threatens to report Ellen to immigration services and Nina lays her feelings bare as she begs him to change his mind. Guppy takes a stand against his father.
Tess and Mike take Sam to see the psychiatrist, Pete turns to Claire for support and an immigration officer questions Abs about Ellen's whereabouts.
Tess is advised to withdraw Mike's treatment and let him die, and Nina administers drugs to a critically ill woman trapped inside a building.
Charlie gives Claire an ultimatum, and Nina learns the landlord is selling the house. Tess considers whether to tell Sam the truth, and Abs receives an unexpected visitor.
Selena turns detective to help estranged husband Will solve a murder, but his bid to repair their relationship fails miserably when she tells him she wants a divorce.