Five-0 discovers the body of a missing 17 year old girl who was kidnapped 10 years earlier, and soon learn that the captors may already have a new victim.
As the older girl was turning 18 and the payments would be stopping, they replaced her with the younger child and killed the older girl.
Mare Winningham guest starred as the woman involved in the kidnappings.
She didn't know what her husband had done to the older girl.
Having had his own daughter go missing last year, Danny, who loves his daughter greatly, does what many of us would be inclined to do.
"Let's just say that the apple doesn't fall far from the tree." Ed Asner reprised his role as smuggler August March, a villain from the original series who become the first non-main character from it to have a rebooted version on the new series when Mc Garrett seeks March's help in apprehending some art thieves.