| Henry Knight |
|Family|| Father (deceased)|
|Behind the scenes|
|Appearances||"The Hounds of Baskerville"|
|Portrayed by|| Russell Tovey|
Sam Jones (young Henry Knight)
- "Mr Holmes, they were the footprints of a gigantic hound!"
- ―Henry Knight [src]
When Henry was a child, his father was killed in front of his eyes when the two were out walking by Dewer's Hollow, the local landmark in his town of Dartmoor. Traumatised, he was convinced a monstrous hound had escaped Baskerville, a government testing site located in Dartmoor, and he moved away. Eventually, his therapist, Louise Mortimer, convinced him to return home to face his fears. Unable to cope and still believing his father to have been murdered, he goes to Sherlock for help in proving this. Sherlock was able to prove that Bob Frankland was the murderer. Henry's father knew too much about Dr Frankland's experiments with chemical weapons and his work with a group of scientists, dubbed "H.O.U.N.D." after the initials of their last names. This was the reason for Henry's rationalisation of the killer, projecting him into a monstrous hound.