Here is the summary of Transformers Prime epsiode 2 from seibertron.com (Spoilers Heavy)
TRANSFORMERS PRIME EPISODE #2 SUMMARY
"DARKNESS RISING" PART 2
Running Time: 22:34 minutes
Episode opens up with a "previously on Transformers Prime" recap of the previous episode.
After the Decepticons retrieved Megatron via the Space Bridge at the end of the previous episode, the Decepticons continue mining for Energon deposits. Starscream informs Megatron about how significant this deposit is and that they have amassed quite a stockpile. Megatron informs Starscream that now that he has returned, he will be issuing the commands. Starscream declares he is Megatron's "humble servant". Megatron tells Starscream that his Decepticon army will come but via a new way of materializing them via the solidified form of the "Blood of Unicron". Starscream refers to Unicron as "the destroyer" and that Unicron's blood is the anti-spark. Megatron refers to it as "Dark Energon" which Starscream says has the power to revive the dead. Megatron states that they only need a cadaver to test it, then asks Starscream if he's willing to make the ultimate sacrifice. Starscream tells Megatron that won't be necessary, then presents the deceased Autobot Cliffjumper as a "welcome home present" to his master. Cliffjumper looks pretty rough.
Cuts to opening credits.
Meanwhile at the Autobot base, Optimus Prime discusses their situation with the Human companions telling them that it would be best if they stayed under their watch. Ratchet disagrees with the decision to keep them there. A proximity sensor alarm starts beeping alarming the Autobots to the arrival of a human government worker known as Special Agent Fowler, who arrived via helicopter. Fowler is the Autobot's liaison to the outside world who only visits when there are "issues", according to Optimus Prime, and that it would be best if the teens do not meet Fowler at this time.
Fowler enters the base via an elevator shaft. When he walks into the base, he starts going off on the Autobots regarding the damage caused in the previous episode in the city as well as reports about a motorcycle of unknown make and model and a black and yellow muscle car racing through the city. The human children watch from their hiding spot. Optimus assures the Fowler that the Autobots have the situation under control. Optimus tells Fowler that the Decepticons have not left. Fowler states that it's time to wake up the Pentagon. Optimus assures Fowler that the Autobots are their best defense against the Decepticon force. Optimus tells Fowler that military involvement will only result in catastrophe and that he cannot condone widespread human casualties. Fowler tells Optimus to handle the situation under the radar or that he will, then he leaves.
Back at the Autobot base, Ratchet curses the "Earth tech" because Cliffjumper's life signal popped back online, said it's not possible for Cliffjumper to come back online; blamed it on problems with the computer system. Optimus Prime, Bulkhead, Bumblebee and Arcee leave via their "Ground Bridge" (a scaled down version of Space Bridge technology, similar to how it worked in "Car Robots" / "Robots in Disguise") which enables the Autobots to travel from their base to anywhere on Earth. Optimus tells Ratchet to prepare the sick bay because they may need it. (This is a great scene with Ratchet's character. He really seems like a cross between his various incarnations - mostly between G1 and Animated. Even his voice is like a happy medium between those respective voices.)
Ratchet and his "human companions" discuss his problems with the Earthen technology they adopted from the mountain base's "previous tenants" -- a former missile silo. Raf resolves some problems that the computer's were having, which Ratchet couldn't believe because it was "complex".
After the Autobots take out the initial wave of Drones, they are met with another dozen or so Drones who begin to attack them. The Autobots transform to battle the Drones. As the Autobots advance further through the mine, they are attacked again as they approach the bottom of the cliff/mine shaft where Cliffjumper was disposed of by Megatron.
Aboard the Decepticon ship floating above the mine, Megatron contemplates how to wield the power of the Blood of Unicron. Starscream informs Megatron that "intruders" have entered the mines. Megatron commands Starscream to ready the ship to leave and to "blow the mine".
Back in the mine, Arcee sees Cliffjumper's body a couple of levels up the mine shaft. The rest of the Autobots give her cover as she attempts to rescue his body. A pool of purple liquid surrounds his upper torso as Arcee approaches. The flooring collapses beneath Cliffjumper's body due to the Drones firing at Arcee. She grabs Cliffjumper's arm as his body falls. As she tries to pull him up, the Cliffjumper creature becomes reanimated, attempting to attack Arcee. The creature screams angrily at her causing her to let go after becoming startled. Cliffjumper's body falls again, then slams into a floor below, bouncing off until it reaches the ground level falling amongst some Energon.
The Autobots watch their poor comrades body as it falls when they hear Starscream laughing above. The Autobots move from their place of cover to get a better view of Starscream, who drops a bomb into the mine right before transforming to escape the mine in order to join Megatron aboard the Decepticon ship. The bomb lands next to some of the raw Energon. The Autobots transform to vehicle form leaving the body of Cliffjumper behind. The bomb goes off, causing a gigantic explosion due to the Energon. Optimus orders Ratchet to open the Ground Bridge to bring them back to base. The blast from the explosion is catching up to the Autobots as they race away from the explosion's epicenter. The Autobots barely escape back to the base.
The humans realize that this is a sensitive moment of defeat for the Autobots so they take off to explore. Optimus then asks Arcee what she saw. She says "Not Cliff', at least not anymore. He was mutated, butchered, something like one of the 'Con experiments during the war." She becomes dizzy and falls. The humans are surprised at how "human-like" the Autobots seem. Raf: "Robots who get dizzy?" Miko: "Robots who have emotions?" Jack: "Robots who can die." Ratchet scans Arcee to determine what is wrong with her. He notices a purple liquid on the back of her left hand. Ratchet asked what it was. Arcee responded that she didn't know ... that Cliffjumper was covered in it, leaking it. Ratchet scrapes it off her hand then orders her to take a decontamination bath.
Arcee pulls into Jack's parent's garage. He gets off Arcee, and apologizes for her "loss". Jack's mom arrives home. She explains that she was worried about him and is concerned that she now has to worry about him driving a motorcycle. The scene ends with Jack and his mom going into the house for the night, leaving Arcee in motorcycle form in the garage.
The next morning, Jack hears Arcee revving up her engine. He complains that it's Saturday and she teases stating that he can watch Saturday morning cartoons back at the base with Arcee. Arcee tells Jack to leave a note for his Mom so she won't worry.
Back of the Decepticon ship, Starscream tells Megatron that he doesn't need to worry any further Autobot interference with "Optimus gone". Megatron questions what evidence Starscream has to make this claim to which Starscream slyly states that he blew up the mine where the Autobots were. Megatron assures Starscream that Optimus is not so easily defeated and that he a millennia's worth of battles to prove it. Starscream expresses his concern that Megatron should take a break for a while; that too much exposure to the Dark Energon could adversely affect him. Megatron tells Starscream that perhaps he had not permitted himself enough contact with the Dark Energon. Megatron then grabs a few shards of the substance, then thrusts it into his own "spark chamber" while Starscream yells his concern that Megatron shouldn't do it without knowing the consequences. Megatron begins trembling as the powers of the Dark Energon begin coursing through his body.
The scene transitions from the energy running rampant through the inside of Megatron's body to Ratchet's computer analyzing the same substance. Ratchet states that the base elements of this goo are like nothing he has encountered. He theorizes that it must be extremely concentrated in order for it to have affected Arcee so rapidly. He complains that results are slow coming without the use of proper diagnostic tools, no thanks to Bulkhead. As he pulls out a small tray of the substance, a small amount drips off the tray onto one of his tools laying on the floor. The substance soaks into the device as Ratchet walks over to one of his computers. The device begins to glow and transform ... growing legs and other parts similar to some of the Allspark creatures from the live action films. The episode ends with the small creature charging the camera.
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