I'm surprised no one has mention this episode, but a real stand-out scene w/Alexandra Moltke was the seance held during the Laura story line to find out from Josette about Laura; Josette spoke through Vicki in French. The actress obviously spoke French herself; she was quite fluent. I was impressed with her acting in that scene.
Like Cassandra, 1795 is a real favorite of mine, and the initial episodes when Vicki first finds herself in 1795 are my all-time favorites. Loved the ending of the first episode, when Barnabas announces that the carriage carrying the new governess has overturned, and Naomi says to Vicki "Young lady, I think you had better tell us who you are, and what you are doing here," and Vicki simply faints dead away from being overwhelmed by it all. This is a classic episode as far as I was concerned.