Not a mystery, or even detective story, just a ghost story

The only "clues" were that a mystic and a stage magician both had the same "vision", a stabbing in the snow, a body in the ice. Both are proven frauds at their trades, but still the visions are fact. How convenient.
How does that rank as a detective story?
The Sally Lockhart character acts likes she's "proven" something when the thugs sent to intimidate her "reveal" that, yes, they are involved in the crimes.
Duh. Who else would want to intimidate her? Then they repeat that scenario with the tycoon, twice. Some detective. If it had been a realistic gang she would have disappeared long before that.