The first episode, "How The Light Gets In" has a number of moments, starting with Aiden performing an impromptu chicken dance in a coffee shop when a pushy customer accuses him of being chicken, continuing through his "mooing" at Poppy, and Daniella wanting to know if she's so boring she needs backup dancers. Then there's this exchange:
Daniella: Sounds logical. So you think the killer was using logic when he put the lightbulb in a boy's chest?
Aiden: Probably not, but I'll start with logic and you can start with evil unicorns and we'll see who solves in first.
And this one:
Aiden: He needs Toby to show him where the thing is? What's the thing? The trophy? The boy says no and..."
Daniella: Whoops, I broke into your house to steal something stupid but now that I've up and murdered you, hey, why don't I screw this lightbulb into your chest?
From "No Traveller Returns", when Poppy and Leo insist that they don't have enough evidence, Aiden replies: "In my day that was what we called a clue. So we can follow up on it." (points to a box of the victim's hatemail) "Unless you'd rather pick a random hater from my big box of fun."
From "Swans", when Aiden grills Clara about her credentials and age.
Aiden: How many psychiatrists get certified before thirty?
Clara: The people I diagnose are certified. I am accredited.
Aiden: How many?
Aiden: Were you one of them?
Aiden: Are you still one of them?
Clara (sounding offended): Are you asking me how old I am?
The list of charges that Aiden rattles off at the end of "The Valley" when they arrest the kids who were running the Gladiator Games:
Aiden: You're under arrest for conspiracy to commit assault, aiding and abetting, obstruction of justice, outdoor drinking, littering, and dueling.
Aiden: It's still on the books. Convincing a person to challenge another person to a duel is a crime.
Aiden demanding to know if Clara, as a doctor, ever had some fun at the expense of her hypochondriac sister. The look on her face says it all.
Aiden and Clara accusing one another of having a "bravery problem" during the shooting in "Voices".