Hawaii Five-0

Steve receives a posthumous letter from his mother, containing a cryptic cipher that may be crucial. At the same time, Danny is assaulted by a relentless murderer who is prepared to kill at any cost in order to steal the same cipher.

The episode titled A ‘ohe ia e loa’a aku, he ulua kapapa no ka moana – translated as “He Cannot Be Caught for He Is an Ulua Fish of the Deep Ocean” – is a single instalment of a programme that falls squarely within the episode genre. Its concise format focuses on a tightly‑woven narrative rather than a sprawling series arc, and the title hints at something elusive and hard to capture, setting the tone for what follows. The story kicks off when Steve discovers a letter that his mother has sent from beyond the grave. Inside the envelope he finds a coded message – a cipher that clearly wasn’t meant to stay hidden. The posthumous nature of the note adds an emotional weight, while the cryptic content drives the plot forward, pushing Steve to unravel whatever secret his mother left behind. Meanwhile, Danny becomes the target of a violent encounter. He’s ambushed by an individual who’s clearly prepared to kill in order to get hold of the same cipher that Steve now possesses. The attack underscores the high stakes attached to the coded information, showing that others will go to extreme lengths to obtain it. Both story threads converge around the mysterious cipher, linking Steve’s personal loss with Danny’s life‑threatening danger.