Unique idea, Lorena Corrêa! I think the only thing missing from the logline is the inciting incident.

"After _________ (the inciting incident/the event that sets the plot in motion), a young orphan country girl tries to unlock the secrets of a vault left by her father to stop a tyrant from taking the throne."

I also changed "must unlock" to "tries to unlock" because it sounds more active.

Hey Maurice Vaughan , thank you for the tip, made some changes, what do you think?

You're welcome, Lorena Corrêa. The new logline is better. One suggestion though: Change "his young daughter tries to unlock the secrets of a vault left by her father" to "his young daughter tries to unlock the secrets of a vault he left behind." You wrote "his young daughter," so we already know he's her father.

"After the baron’s death, his young daughter tries to unlock the secrets of a vault he left behind to stop a tyrant from taking the throne."

OR:

"After the baron’s death, his young daughter tries to unlock the secrets of a vault he left behind so she can stop a tyrant from taking the throne."

I like where this is going Maurice Vaughan. What do you both think of the following? "On the eve of the baron’s funeral, his crafty, young daughter must unlock the secrets hidden within a mysterious vault to foil a malicious tyrant’s plan to usurp the throne."

I really like that logline, Derek C. Block. I would put "tries to unlock" or "attempts to unlock" instead of "must unlock" though." I remember Audrey Knox saying in the Stage 32 Writers' Room that "must" makes it sound like the main character is forced to do something. "The Write Now Challenge: The Logline Review with Literary Manager Audrey Knox" (https://www.stage32.com/webinars/The-Write-Now-Challenge-The-Logline-Rev...)

OMG, both look so good! Thank you so much guys! Maurice Vaughan & Derek C. Block

You're welcome, Lorena Corrêa. :)

Fair point Maurice Vaughan.

Lorena Corrêa, anytime. I think it's a very intriguing idea. It makes me want to learn more...and that is the point.