In the aptly titled “Séance,” there is an actual séance; however, we’ll get into that shortly. First, we meet a few more characters and are reintroduced to one we met briefly in “Night Work.” The latter is the endearingly quirky Ferdinand Lyle (Simon Russell Beale), the curator at the British Museum. We met Mr. Lyle briefly when Sir Malcolm Murray (Timothy Dalton) brought him some unique photographs of Egyptian carvings. Throughout “Séance,” the audience is privy to some disturbing yet intriguing scenes that make it difficult to turn away, in spite of every fiber of your being telling you to do so. One such scene involves Dorian Gray (Reeve Carney) and Brona Croft (Billie Piper).