"A Child's Heart - Part One" is the 962nd episode of Casualty and the premiere of the 30th series. It was preceded by "Forsaking All Others - Part Two" and followed by "A Child's Heart - Part Two". The series premiere two-parter featured all of the main cast members, a rare occurrence. The two episodes also didn't take place on the date they aired, unlike other episodes. Instead, the events took place directly after the series 29 finale, continuing the story in the evening of 23 August.
The script for the episode revealed that the events of the episode began at 22:15 and ended at 00:00 on 24 August. Additionally, it revealed that young Charlie's flashbacks took place in 1964, and the ninteen year old Charlie's flashbacks took place in 1974. However, in the credits for the episode it credits the younger Charlie as being eleven years old, but this isn't possible as it doesn't coincide with the date when he was ninteen or his date of birth, given in "Hidden Agendas". Ninteen year old Charlie's age in 1974 matches with his date of birth providing the flashback took place before his birthday in 1974 as he would have then been twenty.
As Zoe struggles to stay alive under the water, Charlie hears her mumbled cry for help and goes in after her. But no one seems to see him and they start to panic. Max also goes in after Zoe and as Charlie manages to pull her up his life starts to flash before his eyes. Charlie manages to pull Zoe to shore with the help of Max, Big mac and Ethan try to help Zoe out and Dixie arrives soon after. Lily is on hand to receive Zoe when she arrives, But Zoe isn't having any of it, She doesn’t want to be there and it shines through.
Cal tries to help out Charlie as he needs to be treated but he doesn’t want to. All he wants to do is call Louis and find out where he is. When he finally gets through to Louis, Charlie collapse in the corridor. Lofty and Cal manage to find Charlie and have to take him into resus. Charlie isn't having any of it and after thinking he had a heart attack he still tells everyone he's fine but after a few sharp words from Connie he lets Cal treat him properly. Charlie also meets old friend Duffy when she turns up as an agency nurse. With Charlie's History Connie and Cal seem to think he was stupid for going after Connie but it just seemed to be in his nature. Charlie goes into VF and the team are finding it hard to get him back but Connie isn't giving up. Lofty calls Louis and tells him to come in.
Dylan is seen standing on the boat and everyone manages to convince him to jump off he manages to swim back to shore. Ethan tries to help out Dylan back at the ED but he becomes agitated with the noise from the busy ED. Robyn manages to treat Dylan and he seems to be back to work when he treats a pregnant woman.
Rita, Connie and Jacob are struggling back in the over stretched ED with agency nurses as everyone is at the wedding. In a club near by a man is shot by someone in a gang and Jacob takes the opportunity to enforce his gang violence protocol but it doesn’t seem like it is needed in this episode as the rivals only turn up at the end forcing Roxy to go in and finished of Jackson but she's left questioning whether she can go through with it.
Everyone is finding it hard having Zoe and Charlie in resus. Robyn cries a lot, Lofty becomes angry at Charlie for playing the Hero and Cal just seems generally lost. However Max is the most torn up he seems angry at Zoe for cheating on him but at the same time he cares about her so much.