The winter finale of Nancy Drew hearkened back to the beginning in several significant ways. For starters, "The Hidden Staircase" re-imagined the plot of the book of the same name, one of the earliest and most important installments of Carolyn Keene's original series. The episode also delved into Nancy's own personal history; to help find George's (Leah Lewis) little sister (Ariah Lee), Nancy revisited the site of her first sleuthing adventure, when she, at just 12 years old, single-handedly rescued a girl who'd been kidnapped. The encounter reminded her of all the trauma she'd experienced and forgotten about that day and allowed her to strengthen her strained relationship with her father Carson (Scott Wolf). Perhaps the most heartrending moment of the episode came at the end, though, when Nancy discovered a letter her mother had written to her after her health began to decline.

Carson reminded Nancy of the gutting circumstances that inspired the note: When Nancy was just a kindergartner, she could already sense that her mother was becoming ill. "You started asking questions about death and mortality," he explained. "And this was her answer to you." Without even needing to look at the note, he could recite the exchange that inspired her mother to write it all down. Nancy asked her mother what part of heaven she'd go to and if she could give her a map to that exact location, so she could find her later on.

If that wasn't enough of a gulp, Carson then read out the portion of Nancy's mom note when she shared some specific directions about where to find her:

Dear Nancy,

The other day, we were rushing out the door to get somewhere, and you said, "Mommy, when you go to heaven, what part of heaven will you be in?" and I was in a hurry and I said, "The northeast corner. Come on honey, we have to get in the car." I forgot about it until you were half-asleep at bedtime and you asked, "Will you draw me a map of the northeast corner, so I can come find you when I get there?"

I'm still working on the map, but when you get to heaven, ask them where the northeast corner is. And you'll see me sitting under a big green tree, watching you with a smile, waiting for you to come find me. No rush, of course. I love you always, always, always.

- Mom

Ouch, the feels. The emotion of the moment certainly sank in with Nancy and Carson. The two embraced, held hands, reminisced about missing her mother, and decided to be there for one another from there on out. All season long, they've been at odds, but now that Nancy is ready to lower some of the walls she put up as a defense mechanism to shelter herself from the pain of her past, she and Carson have a real chance at a healthier father-daughter relationship.

Of course, it wouldn't be Nancy Drew without one last complication sneaking up to spoil the moment. Shortly after Nancy and Carson reunited, they became separated again after Karen (Alvina August) discovered Nancy's journal full of suspicions about Carson's former ties to the Hudson family and used it as evidence to arrest him for the murder of Lucy Sable. Nancy pleaded with her father to tell them he didn't kill the erstwhile Sea Queen, but when he didn't declare his innocence, whatever bonds they might've built seemed to break instantaneously.

Nancy Drew will return for the second half of Season 1 some time in 2020.

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Scott Wolf and Kennedy McMann, <em>Nancy Drew</em>Scott Wolf and Kennedy McMann, Nancy Drew