Agatha Christie - Hercule Poirot: The First Cases

Story-related; cannot be missed.

Here is a walkthrough of the chapter, including everything needed for achievements.

Great Hall
Talk to the Major - Implicating, Agreeable, Antagonizing
Major Felix Hagen (25G) unlocks
Look at the pamphlet on the table
Look at the note on the wall next to the door to the Butler's Pantry
Interact with the door to the Butler's Pantry
Talk to Archibald on the far left side
Enter the large door on the left to the Salon

Salon
Look at the bottle on the bar
Look at the window
Look at the newspaper in front of Margaux
Talk to Margaux
Talk to Cassandra
Talk to Zakariya

Mind Map - Meet the Guests
"Bottle of alcohol" + "Zakariya is intoxicated"

Mind Map - Circumstances
"Hastily-arranged marriage" + "Gedeon looking forward..."
"Brothers have a history" + "Major doesn't like Gedeon"

Salon
Talk to Zakariya again
Exit back to the Great Hall, then enter the Butler's Pantry in the hallway to the right

Butler's Pantry
Look at the letter next to the sink
Look at the photograph on the table

Mind Map - Staff
"Staff photo" + "Staff rota"
"Insufficient staff" + "Staff termination"
Order and method (15G) unlocks
"Recent staff layoffs" + "Family taking care of money"

Butler's Pantry
Talk to Inge
Exit back to the Great Hall

Great Hall
Talk to Archibald
Enter the Salon

Salon
Talk to Cassandra

Mind Map - Staff
"Forbidden areas" + "Archibald claims..."
"Staff know" + "Cassandra dismissive"

Salon
Exit back to the Great Hall
Go upstairs
Enter the double doors at the top of the screen to enter the Library

Library
Look at the note on the green table on the left
Look at the three books on each of the other three green tables
Look at the book on the bookshelf to the left of the fireplace
Look at the book on the table amid the couches
Look at the book on the booksheld to the right of the fireplace
Look at the book on the bookshelf to the left of the window
Look at the window
Look at the book on the desk in the back right corner of the room
Look at the book in the glass case behind Jackie
Well-read (15G) unlocks
Talk to Jackie
Talk to Ernesto
Talk to Hugo

Mind Map - Meet the Guests
"Hugo resistent" + "Jackie dismisses"
"Ernesto helped out" + "Major supports"
"Family still need help" + "Layoffs related to money issues"
"Major supports the family" + "Major's been around"
"Major is very close to the family" + "Jackie's blackmailer theory"

Mind Map - Circumstances
"Gedeon had one of the Major's cigars" + "The Major wanted to calm down"

Library
Leave back to the First Floor Hall
Go downstairs
Enter the Salon

Salon
Talk to Cassandra
Talk to Zakariya
Talk to Margaux

Mind Map - Meet the Guests
"Major didn't treat Cassandra well" + "Margaux protective"

Salon
Exit back to the Great Hall

Great Hall
Talk to Archibald

Mind Map - Circumstances
"Major views the family..." + "Differing status"
"Possible status drop" + "Potential financial intentions"
"Major thinks the Demirs..." + "The Major intended to warn..."

Great Hall
Go upstairs
Enter the Library

Library
Talk to Ernesto
Exit back to the First Floor Hall
Go downstairs

Great Hall
Talk to Archibald
The Altercation (25G) unlocks