During the long walk back to the TARDIS, The Doctor and Clara didn't speak at all. He was too busy thinking about what was coming in those caves. Once they get back inside the TARDIS The Doctor walks up to the console and starts looking at the monitor. Clara wipes the sweat off her forehead and then walks up to him folding her arms. "So go on then what are these cave things then?" She asks looking at him curiously. He ignores for a minute then turns to look at her, he looks down into her brown eyes as he speaks. "The dark caves Clara are the rejects of galleyfreyan society, The Time Lords developed hundreds of different ways of controlling the fabric of time. Not all of them were used. Some were too dangerous, some didn't work and some like those idiots couldn't use them. So they were thrown into the cave and ignored far away from the civilisation. Of course some were curious about what was in there what kind of powerful technology was in there. Many tried to get in. None were ever seen again. Some believed they were killed by the radiation, others believe they got lost In the caves. Personally I believe the technology was powerful enough to kill them dead In there. We need these crystals, they're very rare like that moron Bokkus said those crystals that have the infinite amount of energy to move anything including a planet. So this will be dangerous understand?" Clara gives him a big grin at his last question and speaks with a hint of cheekiness and sarcasm in her voice. "Are you trying to put me off?" He looks at her surprised at her comment and shakes his head. "Don't be so stupid, I'm trying to recruit you. Now we need to be fast so keep up, if you fall behind you stay behind do you understand?" He glares at her. Clara grins at him giving a playful salute. "Yes sir" He frowns even more as he sets the TARDIS moving.
As the TARDIS lands, The Doctor and Clara step outside. They are standing in a wasteland, ruins of houses surround them and old skeletons line the floors. "Nice place" Clara said with heavy sarcasm. The Doctor rolls his eyes at her. "Like I said these wastelands are out of reach only criminals and mutants come round here" Clara looks around and nods. "Yeah criminals, mutants and the occasional Dalek" She points over his shoulder. He spins round quickly seeing a shell of a badly damaged Dalek. "Oh yeah well remember there has just been a Time War here maybe the Daleks wanted the technology as well. I don't the council would've bothered cleaning up the old poor areas. Hmm doesn't sound that different to London if you think about it" Clara rolls her eyes at his joke , nudging him gently. "Were you actually trying to be funny there?" She asks with a laughs. He simply shrugs. "Thought I'd try it out I won't be doing that again now come on let's get moving" They walk to a tiny hole in a wall that they'd only just be able to fit through. Clara raised her eyebrows looking at the hole confused. "Well to be honest Doctor I was expecting something more impressive" He grumbles audibly and rolls his eyes at her. "My god do you humans have any brain cells. The most important part of Time Lord technology?" He doesn't wait for an answer as he climbs through the hole. Clara grumbles and follows him through and gasps as the cave revealed into a massive area that looked more like a temple with Time Lord Symbols covering the walls. "Bigger on the inside" The Doctor states answering his own question from before. Clara stands up next to him. "Right which way then?" Clara asks looking at him. The Doctor looks around thinking. "We need to get to the deepest point of the cave, that's where the crystals will be so this way." He starts walking down a random pathway. Clara follows him looking around uneasily. They walk for a while without encountering any problems. They eventually reach a large wooden door. The Doctor walks up to it to open it but it wouldn't budge. "Just sonic it Doctor" Clara says simply as she watches him. He looks round at her. "Don't you ever listen it doesn't do wood and anyway it wouldn't work in here" Clara looks at him a bit annoyed. "So that's it? Game over at the first hurdle a locked door?" He grumbles feeling around the door. "Shut up a second I'm busy" He eventually finds a button on the door, he presses and suddenly the whole caves shakes. Clara screams and holds onto the walls. The Doctor doesn't react just watching the door as a monitor appears and a dark shaky voice speaks. "You have tried to pass through this test Random generated questions and puzzles will appear, to pass through you must complete it all correctly in 10 minutes. If you fail to meet these requirements you will be erased from time." The Doctors eyes widen. "Oh of course this used to be the final exam at the academy but was abolished billions of years ago." Clara bites her lip watching. "Hmm yeah no kidding. Well no big deal there's 2 of us surely we can do it" The Doctor shakes his head not looking at her. "No only I can answer if you interfere we fail and I can't afford to be erased from time. If that happens all of reality will die. So no pressure let's just hope I'm as smart as everyone knows I am." The clock starts and a series of puzzles appear. The Doctor instantly sets to work typing out complicated co-ordinates and codes. He quickly passes through loads of tests easily. He then gets to one on how to fly a TARDIS in the correct manner outlined by the high council. At this he slows down a bit mumbling rude words about their protocols and saying how certain things were a complete waste of time when he'd been doing it a lot easier for 2000 years. Eventually he gets passed that section and gets to the last section as the clock reaches the final minute. These last tests were to answer questions about earth and its history and beliefs. To a normal Time Lord this would be impossible. But since The Doctor knew earth better than he did Gallifrey he answered the questions fairly easily. The door suddenly swings open as the clock stop on 0:01 seconds remaining. They both take a big sigh of relief. "Why do we always make these things so damm close?" The Doctor grumbles. Clara laughs a little. "I've been asking myself that for ages." He looks at her and nods as they step through the doorway.
The next room they find is completely empty. The walls are white and there is no furniture at all. The Doctor and Clara both look round confused when suddenly a bright light shines over them and a voice speaks. "Welcome Lord Doctor and human Clara Oswald. This is the ultimate test. Many can fight an opponent in front of them. But few can fight themselves. Your subconscious and memories will be projected back at you putting you in a virtual world with all your past and present. Your job is to fight your way out overcoming any obstacle. To secure your freedom you must beat yourself. Good luck" The Doctor gasps and swears loudly. Clara jumps and looks at him. "Okay Doctor that doesn't sound too bad right?" He frowns at her for once looking scared. "Are you an idiot or something Clara? This was an old punishment for criminals, they were forced to face their wrong doings. If they killed someone they'd face them and then unless they escape their minds would fold in on themselves and implode. The reason this is so bad is we're going into my mind and memories, all 2000 years of them. Every planet, every monster, every bad choice. The Daleks, Cybermen, The Master, The Rani, Davros, Zygons, Sycorax, Racnoss, Slitheen. All of that and so much more is in there Clara." Clara's eyes widen in shock as she covers her mouth. "Oh my god" Is all she can say. The Doctor takes a deep breath steadying himself. "Right well we're here let's do this" The room suddenly turns black and the doctors mind is projected out as they enter the most dangerous place in the universe. The mind of The Doctor.