To its credit, “Elementary” makes a concerted effort to expand the boundaries set by the police procedural genre. Each episode may focus on one investigation—sometimes two—but there is always an extra element added that keeps pushing a separate tale along. This time a variation to the normal proceedings is initiated.

“Dead Clade Walking” opens with quick reminders to small storylines introduced previously.  Sherlock Holmes’ (Jonny Lee Miller) role as a sponsor comes into play in full force while Watson’s (Lucy Liu) newest venture of attacking a chest full of unsolved Holmes cases takes center stage. 

The crime presented this week starts from an intriguing place and disappointingly ends with a simple-minded thud. While sifting through the photos of a murder investigation from three years prior, Watson spots an odd rock in a wall. She consults a geology fellow named Gay, who remarks the chalk-like striations indicate the stone came from the Cretaceous period. A quick scan and discussion with a museum curator later reveals the rock contains the fossil of a nanotyrannus, or a miniature t-rex and is worth an inordinate amount of money. Naturally, the stone is stolen from the police station. 

Meanwhile, Sherlock’s sponsee Randall faces a compromising predicament. His former girlfriend has returned and wants to live with him. However, his addiction occurred largely as a result of his association with her. Sherlock reluctantly acts as therapist during Randall’s trying time by suggesting he cut her off completely. The moment recalls Holmes' relationship with Moriarty (Natalie Dormer) and how even the highly cognizant observer has trouble practicing what he preaches. 

After searching an imbecilic ice cream truck smuggling front—seriously, who sells ice cream in January in New York?—Holmes and Watson move to different modes of finding the precious stone. Holmes contacts an erotic pen pal who gives him a name of an expert in the sale and purchase of black market items, “The Magpie.” When the pair goes to meet this mysterious businessman, he is dead and the rock has been broken, thus destroying the fossil. 

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Holmes, now at a loss for leads and suspects, researches through the night and discovers the Dead Clade Walking theory, which posits that certain dinosaurs survived the horrific comet many believe wiped out their existence. As such, dinosaurs may have existed longer than previously thought. Due to the stone’s composition, Gay and Holmes believe it could prove the theory true. Apparently, this is controversial in the paleontological world.

Again, a lead turns into a dead end. DNA found at the crime scene matches the primary paleontologist in opposition to the theory, but his alibi is confirmed and the idea of a framing surfaces. Further digging occurs and Sherlock cracks the case. The initial curator who identified the fossil made efforts to destroy it in order to save his credibility and that of the textbook he co-authored, which is used extensively in introductory science classes. 

By the episode’s close, Sherlock continues working with Randall. The relationship has altered slightly, as Sherlock took a hard stance when Randall ignored his initial advice. Watson sees the care Sherlock has for Randall and reiterates a theme the show is inserting into the Holmes character: compassion. 

The true potential of the episode, however, lies in the idea of cold cases. Sherlock’s past addiction arises when discussing these former cases and could be expanded upon to shed more light on his past, thus showing how much he has changed rather than having him and other characters simply tell the audience. The idea has been breached, but from the looks of the teaser for next week, the cold cases will remain in the chest for a bit longer. 

Read more by Michael at MHMovieReviews.com.

Reach Staff Reporter Michael Huard here.