The Capture of Cerberus: a Hercule Poirot Short Story

We get re-acquainted with Countess Rossakoff, a special person in the life of Hercule Poirot.

It's the 12th and last story in "The Labours of Hercules."

A chance meeting begins the story. The two pass each other on an escalator going in opposite directions. She says to him that they should meet in hell. Which turns out to be a restaurant / nightclub.

As usual Rossakoff may be playing for the dark side.