Jonny Lee Miller Sherlock Holmes Actor Lucy Liu Joan Watson Actor Aidan Quinn Captain Thomas Gregson Actor Jon Michael Hill Detective Marcus Bell Actor John Noble Mr. Morland Holmes Actor John Heard Henry Watson Guest Star Ally Ioannides Cassie Guest Star Raphael Sbarge Richard Davenport Guest Star Kathryn Erbe Nancy Davenport Guest Star Kristine Nielsen Sheila Underhill Guest Star Sarah Cetrulo Mina Davenport Guest Star Genson Blimline Construction Foreman Guest Star J. Bernard Calloway Vince Guest Star Robert Doherty Executive Producer Carl Beverly Executive Producer Sarah Timberman Executive Producer John Polson Executive Producer Jason Tracey Executive Producer Tamara Jaron Writer Guy Ferland Director