Casualty 30th first look: trailer breakdown

To celebrate the first real teaser for Casualty's anniversary feature, "To Old For This Shift", We analyse the most explosive 30 seconds of Casualty yet!

1: The penny drops?

By the look on Charlie's face, he may have twigged that his colleagues in the ED are up to something...

2: Surprise!

It's partaaaay time! But we can't figure out who looks more surprised - Charlie or Ethan. Has everything gone to plan with the celebrations for Charlie's 30th anniversary?

3: Duffy and Josh!

Aww, isn't it great to have them both back? But wait a minute - something's not right. Why is Josh in uniform?

4: Crashed out

So now we know a little more about what happened after THAT cliffhanger. Connie's been thrown from her car and looks in a bad way. But where's Grace?

5: Sparks fly

An explosive disaster appears to have hit the hospital. What impact will it have on the staff and patients?

6: We have lift-off

An air ambulance responds to an emergency. Could this be a lifeline to Connie or Grace?

7: Up in flames

As Connie's car ignites, is Grace still inside?

8: Mayday! Mayday!

Looks like there's trouble in the air. What could have caused it and what might be the consequences?

9: "You're going to have to go through me!"

Is this the epic clash between Charlie and Jacob that Derek Thompson teased at the recent press event?

10: Things are falling apart

As a massive scaffolding collapse rocks Holby City, why is there a huge chunk already missing from the back of that ambulance?

11: Heavy lifting?

Is that a howl of anguish from Jacob? Or is he flexing his muscles for a heroic rescue from the rubble?

So, what do you make of this - and what else did you spot? Leave a comment on our Facebook page with your theories and don't miss the feature-length special on Saturday 27th August, BBC One. #Casualty30.