A/N: for those wondering why the Jedi -- Obi-wan included -- are so blind regarding Palpatine's identity, here there is my explanation.
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"I wish to come with you, Master," Dwen said as he and Obi-Wan walked onto a landing platform overlooking a docking bay where they could see hundreds of clones board a Republican cruiser.
"I know, Dwen, but it's not possible. Not this time."
"A Padawan's place is at his Master's side, to protect and help him," the boy insisted, stubborn.
Obi-Wan sighed and stopped. He knelt to be at Dwen's face level. "I'm aware of it, and I promise, that once the war is ended, I will take you with me on every mission I undertake. But this time is too dangerous for you to come with me. General Grievous has already killed many Jedi and we need to stop him in order to end the war. You are a good Padawan, but you are still too young to be in the war zone. I would be worried for you if you came with me, while instead I must focus only on Grievous. Do you understand?"
Dwen nodded with his head, his stubborn expression replaced by acceptance and concern.
"Must you really go, Master? Cannot Master Windu go in your place?"
"No, Padawan, he can't. Master Windu has already faced Grievous and has been defeated. We need to send someone that he has never encountered before, someone using a lightsabre form he isn't familiar with—and it's me. But don't worry, I will be back. You won't get rid of me so easily." Obi-Wan smiled, trying to lighten the mood.
"It's not that, Master. It's just…the Force is so dark. I can barely see the light when you are not near me. I-I am afraid the dark will swallow me if I try to meditate," Dwen said in a small voice.
"Oh, Dwen," Obi-Wan exclaimed, fighting the lump in his throat. He sometime forgot how sensitive to the Light side of the Force the boy was. Of course he would feel the Dark side oppress him!
He pulled the child against his chest, hugging him. "Listen to me, Padawan. Don't meditate while I'm away. Play, swim, visit the garden, pick the roya-berries from the trees —do all the things you like more and try not to think about the dark. You can even go and sleep in the Crèche. I know that some of your friends are still there…What do you think? Would you like that?"
Dwen nodded, more relaxed.
"That's settled then," Obi-Wan loosened his embrace and stood up. "I will com Master Neque before I leave, to let him know about our arrangement. Also, I promise you this, Dwen: I will do everything in my power to make the darkness go away."
The Padawan smiled. "I know, Master, I know."
"Good. Now go back to the Temple, Padawan. My shuttle has arrived and I must leave."
"Yes, Master. May the Force be with you." Dwen bowed and walked a few steps away. Then he suddenly stopped, turned around, and ran back to Obi-Wan, giving his Master a strong hug around the waist, before darting away again.
Obi-Wan watched him with affection until the boy disappeared inside the Temple, then his expression hardened.
He had a duty to do. It was time to go and get Grievous and end the blasted war.
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Obi-Wan punched the coordinates for Utapau in the navigation computer and, as soon as his starfighter jumped in hyperspace, he leaned against the seat and closed his eyes.
He wanted to meditate and do a thing he had seldom attempted to do while on Coruscant: he would probe the Dark side to discover Darth Sidious' identity.
Probing the Dark side was not an easy task. It required much concentration and dedication. The Dark side was repulsed by the Light and opposed to it violently. The more the Force user was dedicated to the light, the more painful probing the darkness was.
For Obi-Wan, it was pure agony.
The few times he had tried, he had to soon stop because of the crushing pain in his head. On one occasion his pain had echoed so strongly in the Force, that Mace Windu had barged into his quarters, lightsabre drawn, expecting to find Obi-Wan being tortured by someone.
Another time, Dwen had sensed him and screamed in the middle of a class, begging the master in charge to let him go because his Master was dying.
Part of the problem was also due to the fact Obi-Wan could not lower all his shields and call to him all his entire power while on Coruscant. It had been decided that Obi-Wan would reveal his full power only when the Force urged him to do so, or when the moment to attack Sidious came.
But now he was in hyperspace, far away from Coruscant, thus Obi-Wan lowered all his barriers and opened completely to the Force. He let the Light side fill him, fortifying him for the task ahead.
When he was centred and focused, Obi-Wan concentrated his attention on the black cloud he pictured the Dark side as.
As usual, as soon as he started probing it, the cloud threw against him blue lighting bolts like those that had sprung from Dooku's fingers. The bolts hit Obi-Wan, for he had no defences against them.
His agony was acute. It was like he was being burned alive. The fact that it was only a mental pain did not lessen the impact on his body. His breath was laboured and his heart hammered in his chest, as he tried to advance into the black cloud.
The bolts continued their attack, barrelling over him as Obi-Wan stubbornly pushed forward. The pain was unspeakable. All he wanted was to back away, to return to the safe comfort of the Light side—but he could not. He had to go on. He had to step into the Dark side.
Pouring all of himself into the task, Obi-Wan pressed on, as lighting bolts rained on him from every direction.
Then, suddenly, the attack ceased.
Panting harshly, Obi-Wan looked around himself. He was surrounded by a thick mist, as he had been in that cave on Dagobah. And just like that time, when the fog dispersed, an image appeared—but it was not Bruck Chun.
Obi-Wan saw Coruscant, the Jedi Temple standing tall and solemn and unaware while a whole legion of clones, led by a dark-clad figure holding a red lightsabre, marched toward the main entry, blaster rifles ready to fire.
He saw the crystal world of Mygeeto. A battle was raging across a long bridge. Ki-Adi-Mundi was leading his clone troops forward, his lightsabre deflecting the blaster bolts. Then, suddenly, the clones stopped and took aim, killing the stunned Jedi Master before he could defend himself.
He saw a luxuriant forest of Felucia. Aayla Secura was advancing between the tall flowers with a group of clones, when the soldiers raised their blasters and shot her in the back.
He saw Saleucami. Three speederbikes raced through the desert, Stass Allie was in the lead. Then the two clones following her dropped back and blasted her, causing her to crash against a rock.
He saw the tall trees of Kashyyyk. Yoda was on a balcony, observing the battle raging below. Two clones in mimetic outfits walked behind him, blaster ready to fire, but when they were close enough, Yoda leapt in the air and severed their heads in a blink of an eye.
Obi-Wan would have smiled at the scene—if he still knew how to smile.
He retracted from the black cloud, seeking comfort in the Light side of the Force, shocked by what he had seen.
The clones—rebelling against their commanders. Killing the Jedi in cold blood. Murdering them. Executing them as if they were criminals…traitors.
Who could give them such an order?
The Sith, the Force whispered.
Who is it?
Trust your feelings Obi-Wan, and discover his identity you will, the Force answered, sounding as Yoda.
Obi-Wan's eyes opened, and without thinking twice, he brought his starfighter out of hyperspace. Then he reprogrammed the navigation computer to return to Coruscant as fast as possible. Once back in hyperspace, the Jedi organized his thoughts.
All had started with the Naboo Crisis. The Sith had been behind it; Dooku had told as much to Qui-Gon on Geonosis.
What had been the most immediate and important consequence of that crisis?
Chancellor Valorum had been discredited and Palpatine had been elected. Palpatine had been the Naboo Senator and the crisis on his homeworld had attracted him many sympathies. Perhaps he would have not been elected without the Naboo Crisis.
Then there had been the rise of the Separatists' threats and the war. In words, Palpatine had said he wanted to find a quick solution to the conflict, but his actions had pointed in other directions. He had refused to pursue diplomatic solutions and stood by as new battlefronts opened every day, obliging the Jedi to stretch their resources.
Obi-Wan's eyes widened as he suddenly realized that the war had only been an elaborate trap for the Jedi.
Not only had the Order lost support because of its perceived failure in ending the war quickly, but it also suffered the loss of many of its members. Their numbers were so low that the Council was even thinking of changing the Code to allow a master to take two or three apprentices at the same time.
Also, if his visions were right—and he believed they were—the war had also created the condition for the clones' betrayal. The Jedi sent alone or in pair among hundred of clones would have no chance when the trap would spring…on Palpatine's order!
Palpatine was the Sith Lord! It was so clear now!
Mace Windu had once said they could exclude Palpatine from their suspects because he already ruled the galaxy…That was true, but he also wanted to annihilate the Jedi Order!
And the Jedi had left him free to do it! In the fear of alienating the public opinion, of committing the wrong political move, of being considered traitors, the Jedi had betrayed the Republic, leaving it in the hands of a Sith Lord that had spread war, pain, violence across the galaxy.
Why had they been so blind?
Obi-Wan had no answers, and he knew the Jedi would not have the time to find them if they did not act quickly.
Jumping out of hyperspace, Obi-Wan hailed Mace using their most secure, scrambled security code.
The Korun Master answered at once. "Obi-Wan?" he said, surprised and worried, "Are you already on Utapau? Is there something wrong?"
"There is no time for questions, Mace. Listen to me. Palpatine is the Sith Lord and his next move will be against the Jedi. The clones will rebel and attack their commanders, and will march against the Temple. You must alert all the Jedi on the battlefields of the danger they are in. Call Master Yoda back on Coruscant, we will need him. You must also organize the Temple defences, but do it in secret! Palpatine must not know it. Do you understand?"
"Yes, I do," Mace was shocked, but he was a man of action and he had recovered quickly. He knew the fate of the Jedi was in his hands.
"I'm en route to Coruscant; I will be there as soon as I can."
"All right."
"May the Force be with you."
"And with you, my friend."
Obi-Wan closed the communication, then jumped back into hyperspace.