Why did Frances go to Halliday's?


Hint 1 of 5:
Well, if you know the murderer already, this question shouldn't be hard.

Hint 2 of 5:
Remember that Dr. Trevalyan took care of Loretta.

Hint 3 of 5:
Trevalyan worked at the Mesmer-Braid Institute for a while.

Hint 4 of 5:
And Mesmer was the father of hypnotism.

Hint 5 of 5:
Do you think that Loretta learned a bit of this skill from Trevalyan?