I ducked into the shadow of the building next door. Fran didn’t even glance my way. She was totally focused on where she was going, walking quickly with an evil smile on her face.

I had seen that smile before — when she had talked about taking my cousins’ body parts to build her monster!

Was Fran following the same clue from Dr. Frankenstein’s journal as I was? Did she know how to find Samuel Hammer’s grandson? Was she on her way to him now?

I had to find out.

I trailed her, or tailed her, or whatever you call it as she walked all the way down Grand Avenue. She walked so far that the sun set, and a full moon rose.

My huge feet were aching, but Fran kept walking faster and faster.

Fran marched right up to a building that covered an entire block. Metal letters on top of the building spelled out the words “Los Angeles Convention Center.”

Fran pushed her way through a glass door. I counted to three and followed her inside. And ran right into a man-sized badger!

There were dozens — no, hundreds — of people-sized animals walking around in there!

Were they victims of one of Fran’s insane experiments? What had she done to them?

What would they do to me?

I slowly backed my way toward the door. That’s when I saw the banner hanging from the ceiling. It read, “The Los Angeles Convention Center Welcomes You to THE PROFESSIONAL SPORTS MASCOT CONVENTION!”

Okay, whew! These weren’t half-human animals. Or even half-animal humans. They were people in mascot costumes! I recognized the dolphin from that football team. And the dinosaur from that basketball team. I wasn’t sure what the orange fuzzy thing with the big yellow nose was supposed to be, but I knew I had seen it on TV.

It was actually pretty cool.

Or would have been, if it weren’t for Fran.

She still hadn’t seen me in the crowd. She was too busy looking for someone else.

Which could only mean one thing . . . One of my cousins was inside one of these mascot costumes!

If Fran was following the same clue from Dr. Frankenstein’s journal as I was, she had to be looking for Samuel Hammer’s grandson.

But which one was he?

The mascots were covered from head to toe by their costumes. All you could see of the person underneath were their eyes.

Fran looked at costume after costume. But she didn’t see what she was looking for. Frustrated, she moved deeper into the sprawling convention center.

And that’s when I saw him. He was standing near the men’s room, dressed as a grouper. Or maybe a marlin. Definitely some kind of blue fish.

His eyes were focused on a man dressed as a blue jay. Maybe that’s what made me notice the bright green in the eyeholes of the fish head.

The same bright green eyes as Samuel Hammer! The same bright GREEN as my left eye!

I’d found him!

Now I just had to make sure Fran didn’t.

As soon as Fran was out of sight, I raced up to my cousin.

I didn’t know how long I had before Fran wandered back. I had to warn him now.

“There’s something I’ve got to tell you right away,” I said. “You’re the grandson of Samuel Hammer, the famous detective, right?”

“Shh! Quiet!” whispered the man in the fish costume. “Did the Chief send you?”

“Chief?” I asked, confused. “Wait, you mean that Indian Chief mascot over there? No, I . . . well, this is kind of hard to explain, but my name’s J.D. and —”

“Look, that’s swell. But can you scram?” he replied. “Don’t mean to give you the bum’s rush, but I’m kind of busy here.”

“Actually, no,” I told him. “This can’t wait. See, there’s this girl named Fran Kenstein who is hunting for my cousins. So if you’re the grandson of Samuel Hammer, the famous detective —”

“Detective? Who’s a detective?!” cried a man dressed in a blue jay costume. He had been about to go into the men’s room. Instead, he took off running for the exit.

“Thanks, kid!” sighed my cousin.

“You’re welcome,” I replied.

“No, I meant everything’s all wet because of you!” he exclaimed. “I’m a detective, just like my granddad. And I’m undercover on a case! I was following that guy in the blue jay costume!”

“Oh,” was all I could think to say.

The detective reached inside his fish costume and pulled out a police walkie-talkie.

“All units near the convention center, this is Detective Sam Hammer of the MCU! Requesting backup! Suspect on the run!” he said into his walkie-talkie. “Suspect is approximately six feet tall and dressed as a blue jay. Over!”

The detective put his walkie-talkie down and slipped out of his costume. “The two-time loser inside that blue jay costume is a hood named Lavenza,” he said to me. “I’ve been tailing him for days. Lavenza’s a thug for hire. Big-time crooks call him when they are planning some very bad business. He was just pretending to be a mascot to meet the criminal who wanted to hire him.”

The detective looked at the bathroom Lavenza had been about to enter. “Which means that palooka is probably in there!”

The detective put his hand on the bathroom door. “Stay out here,” he warned me. “It could get dangerous in there.”

He was right. Only the danger didn’t stay inside!

A man in a wolf costume slashed through the door with his claws!

He knocked the detective over.

And then he ran right at ME!!