Guy is held hostage by a grieving widower looking for revenge.

Sacha's world is thrown into uncertainty when an old nursing friend of Essie's turns up.

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.

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.

Operating on an old school teacher, Ric battles to remain in control as Mo learns that she hasn't won the role of consultant as Serena is worried about introducing Robbie to her family.

Bernie has to work alongside an old army colleague and ends up being forced to confront the secrets of the past and face the truth behind her sudden exit from the army as Mr T learns that no one takes him seriously as Serena has a choice to make between her happiness and Jason.

Part one of two. Guy's plans for his much anticipated Neurosurgical Unit are put in jeopardy when he makes a shocking discovery about Tristan Wood - the Unit's main benefactor. Meanwhile, Serena considers re-kindling her romance with a smitten Robbie but, with Bernie in her thoughts, can she commit to happy ever after with him? And Ric is pressurised to undermine everything he's worked for by Tristan.