A new principal character, Jack Turner (Michael Kitchen), was introduced at the start of the series to act as a catalyst between Christine and Robert.

[3] Following the loss of a large chunk of the main cast, the fourth series saw the introduction of twelve new characters, including new senior doctors Ruth Cole (Jaye Griffiths) and Danny Barton (James Murray), with only four of the show's original stars returning.

A largely critical reception for the new cast, coupled with declining viewing figures, were cited as the main reasons for the show's axe.

Robert returns to A&E to show off newborn baby Harry, but ends up getting roped into dealing with two window cleaners involved in a serious accident.

David continues to try to win Yvonne's affections, and Christine has a new admirer in the form of new paediatric doctor Andrew Argyle.

A young female who arrives in the department complaining of abdominal pain is discovered to be pregnant, and with contractions well underway, Robert faces no choice but to deliver the baby himself.

The department is thrown into turmoil when a patient is admitted covered in a mystery powder, forcing Resus to be put into quarantine.

David is forced to deliver heartbreaking news to regular patient Martin, after an X-ray discovers traces of a rare form of bone cancer.

Kate deals with an elderly patient who shows no signs of medical requirement, but is shocked when the woman unexpectedly dies whilst waiting to be transferred onto a ward.

New nurse practitioner Samantha Docherty's first day goes from bad to worse when a man she met the night before whilst out clubbing is admitted to the hospital in the custody of two police officers.

Christine's promotion to consultant, despite being endorsed by Robert, seriously upsets their relationship after she tries to persuade the father of a motorbike crash victim to honour his daughter's wishes by allowing her to be an organ donor.

Christine's relationship with Robert deteriorates, and she accuses him of siding with Jack over the dubious diagnosis of a patient admitted after falling from a motorway bridge.

Sam deals with an infected flesh wound involving a lively young couple who have an uncontrollable urge to make love to each other.

A gas explosion in a poker club results in an influx of injured victims, and David's inability to thrive under pressure is called into question.

Danny Barton's first day goes from bad to worse when he inadvertently informs a patient's relatives of their son's death, despite him having been discharged several hours earlier, and then ends up being held at gunpoint by the father of a young boy who was murdered after becoming caught up in a turf war.

Saskia treats a young woman complaining of abdominal pain, who later reveals that she has taken more than forty pills in an attempt to take her own life.

An elderly patient admitted with a broken arm makes a live television interview claiming that he was assaulted by a group of black youths.