Lestrade: "Holmes! What's going down?"
Holmes: "We are, Lestrade, unless my associate can offer a technical solution to this dilemma!"'
Holmes: "We are, Lestrade, unless my associate can offer a technical solution to this dilemma!"'
- Adapted Out: Helen does not have a twin sister in this story.
- Adaptational Heroism: While still the culprit, Roylott's motives are far more noble than his literary counterpart. Rather than wanting to murder Helen to claim her inheritance, he committed theft to ensure she would have money to support herself and keep his zoo open.
- Animal Wrongs Group: The Earth Sentinals, the group that both Grimsby Roylott and Forest Chapman were a part of in their youth. It's Played With in that the group originally fought for animal rights using relatively normal means like protesting, but when they seemed to be losing progress as species faced extinction, Roylott decided to open a zoo to house and protect as many animals as he could. Chapman, angry that his friend would seemingly imprison animals against their wishes, thought the best method was to create new species for the future by gene-splicing existing ones. Roylott saw this as a cruel affront to nature and the two broke apart, the group dissolving soon after.
- Fluffy the Terrible: The ferocious manticore that Chapman siccs on the detectives? Her name is Agnes.
- Hypocrite: Chapman is quick to call out how Roylott used his snake's DNA and stole his work to turn himself into the very monster he accuses him of creating.
- Mix-and-Match Critters: Chapman's menagerie at his Mythological Museum includes various animals that had their DNA mixed to resemble monsters of ancient mythology. The only ones seen are a gorilla with a scorpion's tail (manitcore), an eagle and lion mix (gryphon), and a three-headed dog (Cerberus).
- Our Werebeasts Are Different: Roylott's snake form has shades of this, though he has the power to control his transformations at will. He's much more powerful than a normal human and can slip through vents and bars better than any contortionist. The only downsides to his new form are his aversion to cold water and his periodic shedding, meaning he has to find ways to dispose of potential evidence.
- Red Herring: Chapman definitely seems to be the most likely suspect behind the Genie Tech robbery, having access to genetic engineering and even floor plans to the building lying around. However, everything is laid out so obviously that Holmes doesn't buy it for a second. True enough, Chapman is being framed by the real criminal.
- Related in the Adaptation: Helen was Roylott's stepdaughter rather than blood daughter in the book.
- Scaled Up: Pinned into a corner by Holmes and Watson at the climax, Roylott angrily transforms into his snake form to make an escape. He looks like a massive snake, but with human arms and can speak. When the group separates, he seizes the moment to try and kill Holmes by suffocating him.
- Snake People: Roylott is revealed to have mixed Monty the python's DNA with his own, allowing him to morph into a naga-like creature at will. His flexible skeleton allows him to slither through tight spaces with ease, though his break-in causes him to scrape off a few of his hair-flecked scales as evidence.
- We Used to Be Friends: Roylott and Chapman were this in their youth, but drifted apart after fighting against whose method better protected animals. The blood between them is bad enough that Roylott doesn't think twice against planting evidence of his crimes at Chapman's museum to use him as his patsy.
