In Episode 4, a significant secret about Alison and Daniel's past is revealed that explains why their teenage romance was cut short. This revelation is central to the episode's emotional climax and forces both characters to confront the truth about their history and the misunderstandings that separated them.

Alison collapses early in Episode 4, leading to an ambulance being called. This health crisis creates urgency and tension, setting the tone for the episode and impacting the dynamic between Alison and Daniel during their tense phone conversation from Sydney.

Music is woven seamlessly into the fabric of Episode 4, serving as a connective thread between past and present. It helps to evoke memories and emotions tied to Alison and Daniel's relationship, underscoring key moments and the emotional weight of the story.

In a flashback scene at The Auld Dubliner pub, young Alison is shown clearing a table and working on a letter to Daniel. During this scene, Mark and another man flirt with her, highlighting the social environment and tensions around Alison at that time.

Daniel is left heartbroken and deeply shaken by Alison's sudden disappearance in 1989. This event profoundly affects him, leading to emotional struggles that are explored in Episode 4 as he grapples with the loss and the unresolved feelings from their past.