It’s Sin City rather than Holby City in this week’s special standalone Casualty episode…

It’s a rainy nightshift at Holby City ED and Dr Ethan Hardy finds himself drawn to a mysterious woman, Bonnie, who may or may not have shot her boyfriend Clyde (ex-Hollyoaks star Stuart Manning) through the heart.

As the shift progresses, Ethan realises he met Bonnie 10 months previously when she was brought into the ED having suffered violence at the hands of her boyfriend, Clyde.

When Clyde doesn’t die from his gunshot wound femme fatale Bonnie seizes her opportunity to see that she finishes what she started. She kills Clyde in cold blood and escapes to a new life. Meanwhile, Ethan’s left to tell the police the entire story…

Elsewhere, Robyn’s accidentally volunteers to help hospital bigwig, Henrik Hanssen, clear cubicles of casualties before the shift ends.

And paramedic Iain is disillusioned with his lot. He spends the shift mulling over his life decisions.