The owner of the voice was a long, low, tan-and-brown snake—a colossal Burmese python, dressed in a black vest and an acid-green tie. His eyes were a deep, alien green that shone with angry clarity as he reared up, looming above Nick and Judy's heads, glaring down at them with an icy venom. A pair of long fangs protruded from his upper lip like twin daggers, ready to inject deadly poison into the flesh of whomever he bit. A brightly-colored red handkerchief protruded from a pocket on his vest. His long, serpentine body wound beyond the confines of the room he was now peeking into, and his overall demeanor was an extremely vicious one; like he was ready to lash out in hate at anyone he saw.

And it was clear that he considered Nick and Judy potential targets as his tongue flicked in and out of his mouth hungrily.

"And who are you?" Nick asked. "You look a little like someone I've seen before... oh, yeah! I think I saw you slithering out of the sewer in Tundratown once."

The massive python glared at Nick with all the malice in the world as he slithered back into a reared-up position.

"I can assure you," the reptile hissed in a surprisingly calm tone, "I am not a sewer reptile. I have something to say that doesn't warrant your cheap jokes."

"Ouch!" Nick said, pretending to be offended. "My jokes are bought at the finest joke store in the world!"

"That might be true," the python hissed, "but you don't choose your company well."

Neither Nick nor Judy understood the serpent's words. But then again, reptiles were usually quite good at speaking in riddles. This python was most certainly good at it.

"I," the python announced, turning to face the crowd of animals outside the cabin, "am Omar Fangzahn, owner of VenomWare electronics and all of its subsidiaries, and can tell you who the killer is, for I saw everything!"

The animals murmured. Judy and Nick both were confused. Dr. Trott, who was busy examining Ms. Frost's body, looked up from the subject of his examination.

Fangzahn, using the tip of his tail, pointed to Ms. Frost's body.

"You!" he growled. "Can you determine what the cause of death was in the victim, please?"

"Well," Dr. Trott explained, "it's a bit hard to pin down precisely what the cause of death was. It could one of a million different things—"

"Just look at her body!" Fangzahn hissed. "What do you see from a laymammal's perspective?"

Dr. Trott, once he'd investigated Ms. Frost's back and arms, announced: "It looks like some kind of heart-attacking poison. You can tell because the victim's arms are so swollen, but I know it's poison because the arteries under the fur of the victim are colored an odd shade of blue."

Fangzahn's eyes lit up like twin green lanterns.

"Friends, onlookers and future prospective customers," Fangzahn announced in his booming Middle-Eastern-accented voice, "it's perfectly eassssy to put together the pieces of this puzzle of murder. It is easy enough to solve, and it all leads to an obvious conclusion. Perhaps you recall a brief spat on the platform boarding the Chordata Express. Ms. Frost had an argument with this young rabbit after a brief altercation. Only this rabbit dropped a toxic chemical on the ground, and only one mammal was arguing with the victim. It is within all reasonable thinking that she easily slipped the poison that killed Ms. Frost into her food or some such thing."

Judy stepped forward, her face covered in lines of indignation, shock, denial, anger, and disgust all at once.

"Are you... Are you accusing me of murdering this snow leopard?" she stammered.

Before Fangzahn could answer, however, a smallish voice spoke up, talking with a very thick urban accent.

"Hey," he asked, "what's going on here?"

Fangzahn looked quite irritated as Gerard, the short, stodgy raccoon conductor dressed in a red-and-gold vest and matching slacks and hat, stepped through.

When Gerard saw the dead body of Ms. Frost slumped over the sink in the bathroom, and the worried face of Dr. Trott standing next to her, he practically had a heart attack.

"Is she dead?" he asked, wildly looking to the nearest authoritative figure for answers.

He probably shouldn't have looked to Fangzahn, but he did. Fangzahn seized the opportunity to continue his riddle-like speech.

"Mr. Conductor," Fangzahn hissed, "she has been murdered, and there's only one animal on this train who had any sort of contact with her. It's plainly obvious that the argument this rabbit and Ms. Frost started on the platform back in Capital City is the direct cause of her death."

"What are you saying, tall-dark-and-scaly?" Nick asked, stepping forward in front of the still-stunned Judy like a personal bodyguard.

Fangzahn continued his riddles as the other animals around the car now turned their gazes to Judy Hopps. It was like they were ganging up on her all at once to defeat the supposed enemy in their midst.

"I know," Fangzahn continued, "that an argument breeds hard feelings between animals, and that there was a mammal here now that was in this car when the murder occurred. There is only one mammal in this car who fits all the criteria of motive, means and opportunity—this little fuzzy rabbit, whom no one would suspect."

Confident, Fangzahn slithered off to the right, eyeing his tail absentmindedly.

"That's not true!" Judy protested, and Nick could quite clearly see the tears in her eyes.

Fangzahn smirked.

"Perhaps," he hissed slyly, "you should never have applied for a job the police force. Besides," he added with a dismissive sniff, "a rabbit will say anything to maintain her innocence."

As one, every animal looking in towards Nick and Judy, from the tiny mouse next door to the pelican leaning out from his upper room, to the biggest rhino in the hallway, turned angry and accusing eyes on Judy. It was obvious by their expressions that they didn't know if Judy was really the culprit, and they didn't care—they trusted Fangzahn's status far too much to believe otherwise.

Several other animals began to murmur in anger and indignation.

"She must be locked up!" a young elk buck cried aloud.

"Trap the murderer!" an owl hooted from his perch above the door transom.

It was obvious that the crushing glares and infuriated cries of the onlookers were unnerving Judy. She seemed frustrated, flustered and utterly vexed all at once, trying desperately to voice her innocence. Her violet eyes, wide with terror, were screaming to be rescued.

And her vulnerability charged up Nick's desire to defend his girl like lightning into a battery.

"Excuse me?" he asked the massive python, who swung around, almost clipping Nick in the face.

At first, Fangzahn was not quite sure Nick was speaking to him.

"Yeah, blinky," Nick said. "I'm speaking to you. I want to make something clear to you. First of all, Officer Hopps and I are both police officers, so, technically, you can't arrest us or put either of us in prison. You're not the officer—we are."

Fangzahn gave Nick a smirk that rivaled a sly fox's.

"Oh, is that so?" Fangzahn asked with a slightly snobbish tone in his voice. "I believe you officers of the police have heard of a certain policy in our state's law—that of the 'citizen's arrest.' If a law officer is not present, or in this case, is the perpetrator of a murder, then a citizen has every right to detain them. I think you might want to check the regulations manuals."

Next to Nick, Judy nodded confirmation, looking more worried all the time.

"D'oh!" Nick grunted. "I knew I should have read the part in the manual covering civilians."

Fangzahn then raised his voice.

"If no one else will step forward to detain this murderer," he announced, "then I will."

He was about to launch himself into the task of placing Judy under arrest when Nick strengthened his wall of defense, desperate to try and stop the huge snake.

"Hey, hey, hey," he said, standing defiantly in the python's shadow. "Bad python! Listen for just a second, scaly. My girlfriend is not a murderer. I already know it, and Dr. Trott already knows it. And if you don't see it, then I'll make you see it. I'll prove it to you."

"What are you saying, Nick?" Judy whispered. Just hearing her vulnerable, quavering voice was enough to steel Nick's resolve to stand up for her all the more.

"I'm saying, Carrots," Nick said, now bold as brass, "that so help me God, I'm going to show you that you're not a murderer. I'm going to clear your name and there's nothing Snake Oil can do about it."

Although he didn't say anything, Nick caught a glimpse of fear in the dark green eyes of the python, quickly replaced by a devious flash of cunning.

"So..." Fangzahn began, "that's how it's going to be."

Nick nodded solemnly.

The python grinned congenially, his tongue flicking in and out hungrily.

"Well," he said, "It appears that you have all the cards."

"Good to know," Nick replied.

"But there's one thing I require before you launch into your little investigation," the snake interrupted. "The Chordata Express takes a good ten hours to speed all the way to Zootopia from Capital City. The train departed from First Station at noon sharp. It's 4:30 now. If, and that's the largest 'if' I've ever stated, you can solve this in the six hours left before we arrive at our destination, and prove unequivocally that your girlfriend is not the murderer, then I will retract my call to have her arrested."

Nick liked the sound of those odds and the time period. However, Fangzahn wasn't finished.

"If you cannot, however," he growled, "I will have no choice but to have her detained and arrested."

Nick's optimism about the odds suddenly died as he came to grips with the reality of what was going on. He weighed all of the options he had and realized that he had only one choice.

"Deal," Nick said, shaking the tip of the serpent's tail in agreement.

"Excellent," Fangzahn said. "As an advocate for criminal justice, I look forward to see the outcome."

Fangzahn winked, and Nick found himself disturbed by it for some reason. It wasn't a devilish wink, but... something was off with that guy. He could tell.

Fangzahn turned to the crowd gathered and told them to go about their business like nothing was going on, although, Nick noticed, that wasn't enough to stop their judgmental staring.

* * *

Judy and Nick were soon left alone with Dr. Trott and the dead body of Ms. Frost, a silence having fallen over them like the calm after a storm.

Or was it the calm before a storm? Nick always had trouble figuring out which was calmer.

The gravity of the situation loomed over their heads. Sure, Nick and Judy had been through a lot together, but neither had never tried to clear the other's name, murder case or otherwise.

Dr. Trott, knowing he would be valuable to the investigation, quickly stepped out to grab his physician kit to begin some other, deeper methods of examination, leaving Nick and Judy alone.

"Are you going to be OK, Carrots?" Nick asked.

Judy took a minute to respond. "I'm fine," she finally said, although something in Nick's heart sensed something was wrong.

"Let's get to work," Judy pronounced strongly. She then busied herself with her work, beginning to go about the task of proving herself innocent.

"I'm right behind you," Nick said, but he wasn't really sure if he could do anything to help his Carrots. Rather than fret over her like an overprotective parent, Nick decided to wait until he knew for a fact she would need help, even if she didn't ask for it.

He knew her life would depend on it.