Next week, Casualty’s new boxset ‘Internal Affairs’ kicks off, which will see the first appearance of Call the Midwife’s Olly Rix as Flynn Byron – who has been confirmed as the ED’s new clinical lead.

However, Flynn first arrives in Holby as a patient, when he is involved in a horrific accident which has big consequences. Plus, what will a flashforward mean for the team?

Here is a round up of the biggest moments coming up in the opening episode:

1. Meet Flynn

The episode introduces viewers to Flynn, a special forces medic who is seen struggling to sleep in early scenes.

He is about to be deployed abroad and wants to spend as much time as possible with his family before he leaves. But he keeps getting distracted by mysterious phone calls and he eventually goes to meet the person calling him in a pub. What is he hiding?

2. Tariq gets a warning

Tariq has had a difficult time lately, after finding out that his dad had confided in Rash about his cancer diagnosis while purposely leaving him in the dark.

He soon has another problem to deal with, as in the ED, Dylan tells him that he’s been coasting at work. Deflated Tariq promises to step up, but he later makes a mistake…

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3. Flynn is rushed to hospital

A catastrophic series of events after Flynn’s secret meeting leads to him being hit by a van. As he wakes up in the middle of the road covered in blood, paramedics Iain and Jacob arrive at the scene.

In an innovative twist, Flynn’s treatment, including his journey to the ED is captured from the patient’s point of view – and viewers are given an insight into his inner thoughts while the team try to save his life.

4. Stevie gets a blast from the past

When Flynn arrives at the hospital, he finds familiarity in Stevie as they went to medical school together. However, the amount of blood on his face means it takes a while for her to recognise her old university mate!

But while he remains in a serious condition, Flynn also makes another big discovery while watching another patient receiving treatment. What has he noticed?

5. A flashforward changes everything

During the episode, the show moves forward in time, and the two-month jump introduces some new stories for key characters including Ngozi, Stevie, Dylan – and of course, newcomer Flynn.

What will be revealed, and what is in store for the ED team in this new boxset?