The episode depicted an incident involving a contaminating agent that caused people who had been exposed to it to experience respiratory problems. Consequently, a quarantine tent was set up outside Holby City Hospital's emergency department, and the staff were required to wear personal protective equipment. It also featured the revelation that Ethan Hardy was the father of Fenisha Khatri's unborn child as well as the return of Philip Wright as Graham Kirkby.
Due to the episode being scheduled to air during the 2020 coronavirus pandemic, the BBC deemed the episode inappropriate for broadcast due to its content and pulled it. In its place, the following episode aired in its place with an extended recap segment at the beginning showing significant events from the dropped episode.
- George Rainsford as Ethan Hardy
- Olivia D'Lima as Fenisha Khatri
- Jack Nolan as Will Noble
- Shaheen Jafargholi as Marty Kirkby
- Gabriella Leon as Jade Lovall
- Uriel Emil as Lev Malinovsky
- Philip Wright as Graham Kirkby