This was another 'what if?' I thought of and wanted to explore. The timeline is very different from the main canon. In this timeline Yoruichi and Urahara were captains much closer to the beginning of Bleach.

Rangiku Matsumoto stared long and hard at the report before her. She and her captain had not concerned themselves with the intruders into the Seretei as the other captains had. They had taken on the work of the Fifth Squad following the death of Captain Sosuke Aizen, whose murder they were investigating. In addition, that had tracked down two of the three lieutenants who had escaped custody as well as Captain Gin Ichimaru, the prime suspect in Aizen's murder.

There had simply not been time to read every report on the intruders, which was why Rangiku was only seeing the report now.

She wondered whether she should share the report with her captain. They had uncovered evidence that the execution of Rukia Kuchiki was part of a plot to overthrow the Soul Society, and with the announcement that the execution was being moved forward again, they did not have time to waste on distractions.

If it was a distraction.

She walked into the captain's office with the report.

Captain Toshiro Hitsugaya sat at his desk, frowning. He bore a small bandage just above his eye where he had received a small wound in his recent battle with Ichimaru.

He nodded at her arrival instead of greeting her as he usually would. There were so many things he was dealing with at that moment, Rangiku realized. The murder of his comrade, the plot against Soul Society, the execution, and the turning of his childhood friend against him. She felt guilty adding yet another burden.

"Sir, I was going over the reports on the Ryoka, and I found something interesting."

"What is it?" Toshiro sounded disinterested despite the question.

"Captains Kuchiki and Ukitake encountered several Ryoka by Rukia Kuchiki's cell the other day," she explained. "Most of the Ryoka were captured, but one escaped … with Yoruichi Shihoin."

Toshiro's head jerked up in surprise at the mention of that name. "She's here? In the Seretei?"

"That's what the report says."

He got up and turned to look out the window. "Why did she come back? And why now?"

"She apparently said that she means to train the Ryoka to defeat the captains."

He shook his head. "There has to be more to it than that."

He closed his eyes, and Rangiku waited. She knew he was wrestling with conflicting emotions while considering what options he had.

Finally, he turned to her. "Rangiku, I need you to stay here and protect Momo." He began to leave.

"But sir, what are you going to do?"

"Whatever I have to, to put an end to this madness," he answered before flash-stepping away.

Yoruichi watched as Ichigo Kurosaki battled against his zanpakuto spirit. There was now less than a day before Rukia's execution, and he still had yet to achieve his Bankai.

Nearby, Renji Abarai was also training to unlock his Bankai. It appeared to Yoruichi that Renji would reach his goal first. She was beginning to wonder if Ichigo would make it in time.

Not for the first time, she cursed Urahara Kisuke for his vague plans. Even if by some miracle, Renji and Ichigo defeated Byakuya Kuchiki, it would not help them against their true enemy.

Suddenly, her eyes widened as she sensed an immense power approach. She turned to look at the entrance to the cave. Renji and Ichigo, both less attuned to sensing reiatsu, noticed a split second after she did.

"Oh, no." Ichigo whispered to himself.

The figure which had appeared at the entrance to the cave was small, but there was no mistaking the white captain's haori he wore.

"Captain … Hitsugaya …" Renji said in fear.

Ichigo instinctively reached for the nearest sword. He had hardly pulled it out of the ground when Yoruichi grabbed him and slammed him into the cave wall.

"Y-yoruichi…" Ichigo stammered in shock as she continued to pin him against the wall.

"Don't you ever pull a sword on him again," she said in a threatening voice.

"Do you really think he could defeat me?" Toshiro asked as he walked further into the cave.

Yoruichi dropped Ichigo. "As he is now, definitely not."

"So it is true," Toshiro said, looking at Ichigo. "You're training the Ryoka to defeat captains."

"Only if he has to," Yoruichi said.

Toshiro addressed Ichigo. "What is your goal, Ryoka?"

Ichigo stood up and looked at Toshiro defiantly. "What does it matter to you?"

Toshiro's hand moved towards the sword sheathed on his back. "Because your answer will determine whether or not I cut you down here and now."

"Captain," Renji interjected, "let me explain!"

"Be quiet, Renji!" Toshiro growled at him. "You are in enough trouble as it is."

Renji gulped and backed away.

"Well, Ryoka?" Toshiro asked again.

Ichigo refused to be intimidated by the young captain's glare. "My only goal is to save Rukia."

Ichigo and Toshiro continued to stare at each other for several tense seconds.

Toshiro moved his hand away from his sword. "Then we share a common purpose."

He looked at Renji. "And that explains what you're doing here."

Yoruichi breathed a sigh of relief, to Ichigo's surprise.

"For a captain to want to stop a legal execution," she said, "there must be something more going on."

"I was hoping you could tell me," Toshiro said. "I have reason to believe the execution of Rukia Kuchiki is part of a larger plot against the Soul Society. This plot has already claimed the life of Captain Aizen."

Yoruichi looked down. "Dammit."

"What is it?" Toshiro asked.

"We need to talk," she said seriously, "in private."

Ichigo collapsed against the cave wall. He had continued his training while Yoruichi and the small captain went out and talked. And he was now exhausted.

Yoruichi nodded at him as she walked by. "Get some rest. Tomorrow is the day you rescue Rukia."

Ichigo looked up at her. "Is that captain going to help?"

Yoruichi looked to the side. "If you mean 'is he going to fight Byakuya Kuchiki for you,' then no. His part in this is different from yours."

Ichigo could see that the subject of the young, white-haired captain bothered the otherwise cheerful Yoruichi.

"Who is he?"

To his surprise, Yoruichi sat down next to him, placing her chin on her knees.

"Toshiro Hitsugaya," she said. "Child prodigy. Youngest person to graduate the Shinigami academy. Wielder of the most powerful ice-type zanpakuto. Youngest Shinigami to achieve Bankai. And the youngest person ever appointed a captain of one of the Thirteen Court Guard Squads."

"And my son."