Karth House & Mary Meehan Walkthrough Part 3
Walkthroughs for Blackwell Epiphany
Getting Rosa Inside & Meeting Mary
Because this puzzle is being solved by Rosa and Joey working together, you will unlock the Steam Achievement Teamwork automatically when Rosa enters Karth House.
Send Joey back outside to Rosa. After their short dialogue have Rosa look at the graffiti on the lower right wall of Karth House. It's the same as that drawn on the wall inside. Click on the brick with the word Joey saw underlined inside.
When Rosa comments that it's frozen. Have her use her coffee on the brick. After that, click on the brick again. This time it will be removed to reveal a key. Take the key and use it on the front door of Karth House.
With Rosa inside you'll need to take her to the bottom of the stairs near the graffiti. There is a small box at the bottom of the stairs that Rosa needs to search in order to find a Fuse, which you will need shortly.