She looked at him for a long time. “Mac, don’t try to pull anything cute on me.”

“My gosh, what would I pull on you!”

“This isn’t a game, like your apeman stunt. We’re not going to have any code words in Turkish or wear disguises or meet in mysterious bistros. It’s going to be a lot of footwork and maybe nothing but blisters to show for it. If you understand that and still want to come in, all right. Anything else, I go it solo.”

“I hope you’ll put a skirt on, or at least long pants,” the giant said morosely. “Where do we start?”

“We should have started on that dead dog. Long ago. Where it came from, who owned it, how it died, and all that. But now that’s as cold as I am... I’d say, Mac,” said Laurel, leaning against the jamb with her hands in her pockets, “the arsenic. That’s fresh, and it’s something to go on. Somebody got into the kitchen over there and mixed arsenic in with Roger’s tuna. Arsenic can’t be too easy to get hold of. It must leave a trail of some sort.”

“I never thought of that. How the dickens would you go about tracing it?”

“I’ve got some ideas. But there’s one thing we ought to do before that. The tuna was poisoned in the house. So that’s the place to start looking.”

“Let’s go.” Macgowan reached for a dark blue sweater.

“Now?” Laurel sounded slightly dismayed.

“Know a better time?”