Sorry for the wait, I had a hectic day and then had to go to work. So here's the chapter you guys have been waiting for: the Kamen Rider Club is joining the party!

DISCLAIMER: I don't own Criminal Minds or Kamen Rider Fourze.

WORD COUNT: 2258

Friday, February 20th, 2015

No one was certain where it'd gotten out of control. Maybe it was when De Luca had accused Mahoney's daughter of collaborating with his traitors. Or maybe it was when Ulick Vincent, one of Mahoney's lieutenants, had threatened to shoot one Jackknife for getting too close. But everyone could agree that by the time Bertoldo De Luca's bullet slammed into Teague Mahoney's chest, there was no hope of the two gangs coming to a peaceful agreement.

Siobhan had screamed, diving towards her father's body, but Keegan Hayes had grabbed her and dragged her, kicking and screaming, behind cover. She saw Connor and Carbrey activating their Switches, becoming the Lupus and Auriga Zodiarts and charging into the fight. One Jackknife fell under Lupus's claws, another dropped his gun to grab at Auriga's whip after it wrapped around his neck. Another member of her crew managed to hit De Luca in the leg, but was gunned down before he could get back behind the crates he was using for cover.

In the end, the Jackknives retreated; she could hear Ulick calling for the other Seaimpíní to pull back, to not follow. Teague Mahoney's body laid amongst five others on the warehouse floor. Only one of them was a fellow Seaimpíní, the rest were Jackknives. De Luca had gotten away, unfortunately. Siobhan was forced to leave them behind as police sirens sounded, vowing vengeance.

She now had the names of all of Aita's co-conspirators, and where to find them. That information would not go to waste.

The BAU and Ryūsei were less than pleased at the sight of the carnage before them. "This is definitely getting out of hand," Kate stated the obvious, "One or both of the gangs are going to go on a spree, at this rate."

Morgan shook his head. "De Luca probably called a meeting after we told him about Aita. He clearly didn't know about them until we presented the information to him."

"He's the kind of guy who's concerned with his own survival over all else," Rossi profiled, "He believes that the feud should be between the Seaimpíní and Aita's faction, since he didn't start it, and went to throw them under the bus."

"The Seaimpíní likely wouldn't have cared, though," Reid continued, gazing at the sheet-covered body of Teague Mahoney, "De Luca ordered the deaths of two of their people, whether he started the fighting or not. There are four dead bodies from the Jackknives, but only two from the Seaimpíní. The two Seampíní and one Jackknife appear to have been killed by gunshot wounds, but the remaining three sustained wounds similar to Lamberti, Innocenti, and Orlando. I'd say these were killed by the same Switchers, so that means we still have at least two Zodiarts running loose."

Ryūsei shook his head and pulled out his cell phone. Eight more people had died since he'd arrived, more than doubling the original body count. This was getting way out of hand. "That's it," he declared, "I'm calling in backup. I'm not losing another person to this."

He dialled the number for his immediate supervisor in Interpol. "It's time," he told the man, "Call in the consultants. I need them in Boston as soon as possible."

Saturday, February 21st, 2015

Agent Hotchner accompanied Ryūsei to the airport to pick up the rest of the Kamen Rider Club. Garcia had practically had to be restrained from going, wanting to meet another Kamen Rider, but Ryūsei had assured her that she'd be meeting him once they got back to the FBI Field Office. She was still combing through the old security footage, having identified the van in which the Foundation X operatives had arrived to sell the Switches to Aita's crew, and was now searching for it in older footage in hopes of pinpointing when they'd made their transaction with the Seaimpíní. The odds were slim that they'd used the same alley and the same van, but it was the only lead they had right now. The other agents were working with Boston PD, primarily the officers who'd been investigating either gang prior to the introduction of the Switches, to try and identify the Seaimpíní Switchers by figuring out who didn't have alibis for the three unsolved murders.

Ryūsei had to fight to keep from bouncing in anticipation as he searched the de-boarding crowd for his friends. It had been far too long, in his opinion, since they'd all been together. With their jobs and conflicting schedules, arranging reunions had been a hassle. Even though they were coming in to do a job, it was kind of like old times. Actually, the fact that they were reuniting to fight evil made it just like old times.

"RYŪSEI!" Gentarō was the first to emerge, jumping up and down in delight. And he was planning to be an educator! "RYŪSEI! Long time, no see!"

JK was the next person he spotted, if only because his tendency towards bright, gaudy colours had hardly diminished in the past couple of years. He and Gentarō had no problem getting into Ryūsei's personal space, and neither did Yūki, who popped out from behind JK and joined the group hug.

Shun and Kengo were a bit more restrained, but both were grinning as they shook his hand and clapped him on the back in greeting.

Miu gave him a hug and a quick, friendly peck on the cheek, beaming as she ushered Tomoko forward.

Tomoko. She was the one he'd been the most anxious to see again. They'd started dating only a few months after Gamō's defeat, and had been together ever since. Keeping their relationship going long-distance hadn't been without its difficulties, with his job keeping him out of the country as often as not, but they'd made it work. She hugged him tightly, and he held her close and breathed in the strange, yet enticing scent of her homemade perfume – he was afraid to ask what was in it, but it smelled much better than her other concoctions, so he didn't complain.

"Agent Sakuta?" Agent Hotchner's voice interrupted them, "If you could introduce me to your friends?"

Ryūsei and Tomoko reluctantly pulled apart. "Uh, right. Guys, this is Agent Hotchner, he's the leader of the FBI team we'll be working with. Agent Hotchner, these are my friends Gentarō Kisaragi, Yūki Jōjima, Kengo Utahoshi, Miu Kazashiro, JK – seriously, he won't answer to anything other than JK – Shun Daimonji, and Tomoko Nozama." He said the first sentence in Japanese, as the Club members were at varying levels of English competency. Shun and Kengo were actually quite fluent, Yūki, Miu, JK, and Tomoko had been good enough to pass their English classes in high school, and Gentarō was still utterly hopeless with the language.

"How much do you all know about the situation?" Hotchner asked them.

"Ryūsei told us everything over the phone last night," Kengo replied, speaking for the whole group, "We're ready to get to work."

Tomoko couldn't help but feel a bit overwhelmed when they got into the command centre the FBI had set up. She'd managed to pass her English classes with decent grades, but that had done nothing to prepare her for the busy office full of government officials speaking way too quickly for her to keep up. She stuck close to Ryūsei the entire walk through, until he brought her over to a setup with multiple computers, occupied by only one other person. Ryūsei had explained what Garcia-san was doing, so Tomoko joined right in. The two women couldn't have looked any more different, with Tomoko's dark, gothic look and the FBI Analyst's blonde hair and bright, eye-catching colours, but once they sat down at their respective computers, the two hackers got into perfect sync with each other.

The rest of the Club spread about assisting the other BAU members. Dr. Reid and Kengo got to discussing the physics behind the Zodiarts, and it was all anyone else could do to keep up. JK and Miu were sending the Foodroids (which garnered flabbergasted looks from nearby agents) out on recon in areas that were known Seaimpíní and Jackknife hangouts while Yūki monitored their progress on Kengo's computer. Gentarō was really more of a field-action type, so he mostly hung out and watched, with Shun translating for him whenever he had questions.

Ryūsei was more than amused at the FBI agents' reactions to the Kamen Rider Club. They'd had more reason to take him seriously as an Interpol agent, but none of his friends had gone into the professional bad-guy-catching business after high school, so he'd been worried that they wouldn't get the same respect. Thankfully, once they got over the initial surprise, the agents seemed willing to accept any help they could get. He could understand how difficult it was to believe, though, that this mismatched group had teamed up to save the world.

Things got disturbing when the autopsy results on the mauled Jackknives from the previous morning came back – the claw marks and leftover hairs found on their bodies were consistent with the ones on the police officer who'd been wounded responding to the attack on Nicomede Orlando, but not the ones on Orlando himself. That meant that there were at least three Zodiarts running around, not two.

After a few hours, Ryūsei and Gentarō joined Agent Morgan on a patrol of some notable areas of Jackknife territory, in case the Seaimpíní staged another attack to avenge Teague Mahoney.

And they did, but not where the FBI and the Club expected – they attacked the city jail.

When Ryūsei's group arrived on the scene, they found a half-dozen injured or dead guards in the front room, which had been trashed. Ryūsei and Gentarō wasted no time putting on their Drivers as they raced through the torn-open door, following the crashes and yells while Morgan tended to the wounded until more help arrived. A few detainees met them, evidently attempting to escape, but the two Riders managed to knock out any they encountered. They reached the cafeteria and found a scene of chaos; the attack had happened during lunch, so trays, food, and tables were scattered, as were the prisoners who were frantically trying to get away from the three – not two, but three – Zodiarts trashing the place.

A tan, humanoid Zodiarts (Auriga) with wheels attached to his calves and a long, leather whip had said whip wrapped around Cirino Acqua's neck, and was shouting furiously. A grey, wolf-like one (Lupus), had Rosalinda Cavallo backed into a corner and was advancing threateningly. And the third was a hulking bear Zodiarts (Ursa Major), growling as he scanned the crowd of inmates for someone.

"Oi!" Gentarō shouted, getting their attention. It worked; all three Zodiarts twisted around to glare at the newcomers. "Why don't you pick on someone your own size?"

They obviously didn't know exactly what he was saying, since he wasn't speaking English, but they clearly understood the basic message, because they all began to advance on them. Cavallo was able to slip away with Lupus distracted, but Acqua still had Auriga's whip around his neck and couldn't go anywhere.

Both Kamen Riders began to activate their Drivers:

'Meteor On! Ready?'

'Three! Two! One!'

"HENSHIN!"

The Zodiarts and the scarce remaining inmates in the room shielded their eyes from the flashing lights as Kamen Rider Fourze and Kamen Rider Meteor completed their transformations.

"UCHŪ KITAAAAA!" Fourze shouted, sticking his fists into the air.

"Omae no sadame wa ore ga kimeru,"* Meteor declared coolly.

They charged forward, Meteor aiming for Auriga and grabbing at the whip to try and free Acqua while Fourze took on Lupus and Ursa.

He managed to get a strong grip on the whip, kicking Auriga in the face to stun him. With the whip suddenly slack, Acqua was able to unwind it and took off, choking and practically tripping over himself. Auriga let out an inarticulate scream of rage and tried to chase after him, but Meteor refused to let him pass, dropping down with a sweeping kick to trip him. Auriga rolled and got back up to his feet. The wheels attached to his legs suddenly expanded so that they lifted him off the floor, and he shot forward as if he were roller-skating. He crashed into Ryūsei at high speed, slamming him into the cement wall.

Fourze wasn't having much luck, either, as he was facing two opponents by himself. Lupus was fast, dodging all of Fourze's punches and kicks and ducking in to strike when he saw an opening. Ursa was a bit slower, but the hits he landed packed a wallop. He had the Shield and Spike modules activated, fending off an attack from one Zodiarts while kicking another and letting the sharp spikes do their damage. But he was tiring out trying to keep up with them. Eventually, he took a powerful blow to the stomach that sent him flying and crashing down on a table, which broke underneath him.

Both Kamen Riders struggled to stand as their enemies advanced upon them.

*Fourze and Meteor's post-transformation catchphrases, meaning "IT'S SPACE TIIIIIME!" and "Your fate is mine to decide"

And preview for the final chapter:

"She's entered Last One!" Kengo gasped.

"Wait!" Fourze yelled, running forward to try and grab the Switch. But it was too late, as Siobhan pressed the Switch and was immediately enshrouded in dark energy. Her body, now wrapped in a thick, white, cobweb-like substance, collapsed at the feet of the Ursa Zodiarts.

"Revenge…" Ursa growled before charging forward. Fourze put up his Barizun Sword in defence, but he wasn't prepared for the sheer force of the huge Zodiarts barrelling directly into him. He was launched backwards, just missing JK (who screamed and dove for the floor) and crashing into the opposite wall. "Reveeeenge!"