The name Cormoran appears in Cornish folklore. He was a giant who lived in a cave on St. Michael's Mount off Cornwall's southern coast. 18ft tall he used the low tide to access the countryside and pillage the local community until he met his match in "Jack the Giant-Killer", a trapping pit and a mattock (pickaxe).
In the show, Strike is portrayed as having lost his left leg in an explosion whilst in the army. In the books, however, it was his right leg.
The scar on Strike's upper lip is not a part of his literature characterisation, but rather the real scar (repair of a hare lip) of actor Tom Burke.
The author Robert Galbraith is the pen name of J.K. Rowling author of the Harry Potter series.
The concept of Strike literally speaking to his prosthetic leg was added to the TV adaptation as a way to present some of his "inner monologue", of which there are many in the novels.
Although not explicitly shown, Strikes favourite drink is Doom Bar Ale (brewed and bottled in Cornwall).
In the books, Robin does not find out that Cormoran has a prosthetic leg until the very end of the first novel. His sister Lucy mentions that he left the military because of his leg, but does not elaborate further. In the show, Robin learns about Strike's leg very shortly after meeting him, while she is researching Strike on her first day of work.
Elarica Johnson (Lula Landry) has been tied to another J.K. Rowling project; she played the waitress, a character created for the film version of Harry Potter and the Half-Blood Prince (2009)
Both leads have worked very closely with Luke Pasqualino before. Tom Burke in The Musketeers (2014) and Holliday Grainger in The Borgias (2011).
Alan Rickman who played Severus Snape in the Harry Potter series is godfather to Tom Burke who plays the titular character, both JK Rowling adaptations.