"The Ties That Bind Us - Part One" is the 447th episode of Casualty and the first episode of the 19th series.
Abs is consumed by guilt as news of Simon's death begins to spread. Two children go missing after visiting a relative at the hospital, and suspicion soon falls on a local convicted paedophile. When one of the youngsters is found trapped in an underground drain, Nina ignores Luke's pleas to wait for the fire brigade. Selena is now married and she comes back to Holby.