Robert B. Parker on the Big "Aha"

In the following section, the first-person narrator is Spenser, a private detective, who is interviewing the madam of a high-end prostitution ring.

***

"Who else?"

"He never said, but he was quite odd [...]"

"Tall and slim? Chewed gum?"

"Yes."

I said, "Aha."

"Aha?"

"Yeah, like Aha I see a connection, or Aha I have discovered a clue. It's detective talk."

[...] She sipped some more Campari. I drank some Heineken. "Among my enterprises," she said, "is a film business. This gentleman had apparently seen Donna in one of our films and wanted the master print."

"Aha, aha!" I said. "Corporate diversification." The waiter came for our order. When he was gone, I said, "Start from the beginning. When did you meet Donna, what did she do for you, what kind of film was she in, tell me all."

"Very well, if you promise not to keep saying Aha."

--Robert B. Parker, Mortal Stakes (1975), pp. 146-147.