Now that MEGATRON is out of the picture, STARSCREAM returns to CYBERTRON to take over the DECEPTICONS and become their leader, which most are cool with, MEGATRON was getting a little to tyrannical for their tastes.

With the ALLSPARK destroyed, CYBERTRON is headed toward certain doom. An energy source has been located on Earth that can save their world and STARSCREAM and his DECEPTICONS are determined to rob Earth of it.

MEGATRON still has a loyal faction with SOUNDWAVE as the leader who are determined to resurrect MEGATRON, head off STARSCREAM and get the energy source for themselves.

There is a spy amongst them, HOT ROD gathers intel and returns to Earth to report to OPTIMUS PRIME and the AUTOBOTS about the plans of the two DECEPTICONS factions.

SOUNDWAVE and his army gain control of the NEMESIS and escape the battle with STARSCREAM. They head to Earth.

Back on Earth, SAM WITWICKY has gone off to college in New York with BUMBLEBEE in tow. MIKAELA is still in California with Prime and the other AUTOBOTS.

SOUNDWAVE and the NEMESIS arrive on Earth and plunge into the ocean. An aircraft carrier is capsized from the force and the NEMESIS scans and transforms into a carrier with the DECEPTICONS on board transforming into various military vehicles.

SOUNDWAVE is a high-priest in MEGATRON's court and is a healer of sorts and will be the one to bring his lord MEGATRON back to life. They find him in the ocean's depth and the resurrection begins.

HOT ROD has returned to Earth, he gives PRIME and the others the lowdown on the plans and tells them the coordinates of the secret energy source located on Earth. It's none other than Las Vegas.

After a quick street race with BUMBLEBEE and SAM being the winners (of course) SAM is notified of the imminent invasion and heads to Las Vegas. SAM's Asian dorm roommate named SHIGE who is with him is unknowingly in for the ride of his life!

We are given some background on the First Seven here, who were introduced in the first film. Apparently, they managed to harness the energy of the ALLSPARK into a secondary source that will provide energy for generations. This energy orb is located underground spanning from Las Vegas to the Hoover Dam, this is what the DECEPTICONS are after.

In Las Vegas, MIKAELA finds Agent SIMMONS at the Luxor, the access point for the energy orb located beneath it. An evacuation plan is put into action for Vegas and the military is called in. They meet up with ELLISON a descendent of one of the original seven who knows more than he should.

Next, we are given some details on how the giant robots are brought to life. The ALLSPARK gave them their life but something called The MATRIX gave the robots their soul. That's why the cell phone little robot in the first one was evil to begin with, it hadn't been given a soul after coming to life. It has been passed down through the years with the ORDER OF THE PRIMES and OPTIMUS is the one currently in possession of it in his chest.

Though SOUNDWAVE has brought MEGATRON to life, he needs the energy of The MATRIX to make his resurrection complete, for now, MEGATRON is dependent on SOUNDWAVE for his energy.

SAM, BUMBLEBEE and SHIGE are the only ones headed West bound to Vegas as people are pouring out due to the evacuation. Up ahead are six construction vehicles who begin to transform. They fit together to form one, DEVASTATOR. This monstrous robot begins to chase after SAM and crew.

Help arrives in the form of ULTRA MAGNUS and his team who help SAM get away and get to Vegas where the other AUTOBOTS and the US Defense has gathered to stop the invasion.

STARSCREAM and his army are seen dropping to Earth. They are headed off by some AUTOBOTS in the sky. They fall to the ground fighting.

The DECEPTICONS continue to attack and they have a new force field around them that the militaries high heat rounds have no effect on.

ULTRA MAGNUS, SAM and team arrive in Vegas. Magnus and crew join the fight. SAM heads down into the bunker where MIKAELA, SIMMONS, ELLISON and others are hiding.

SKORPONOK returns and burrows his way into the underground tunnels/bunker where they are hiding, also where the energy orb is located.

The military is awaiting reinforcements and they arrive in the form of jets and what not. The pilots are about to start dropping bombs when their aircraft begin to transform, they have been compromised and MEGATRON and his loyal army are on the move.

With the war turning badly for the AUTOBOTS, ELLISON and SIMMONS know there is only one thing left to do. Atop the Stratosphere is a Sector Seven EMP that is waiting to be activated in times just as these.

ELLISON and the EMP team, escorted by AUTOBOTS, are headed to the EMP to activate it. SOUNDWAVE intercepts the plans and heads out to stop it. The EMP team is struck down and only ELLISON is left. But he is in no condition to get to the top of the tower, SAM and MIKAELA go it alone getting instruction via walkie-talkie from ELLISON.

A DECEPTICON tries to stop SAM and MIKAELA and creates a gap that SAM cannot get over, MIKAELA must go to the top by herself. MEGATRON then unleashes a missile attack on the Stratosphere and there is a huge explosion, MIKAELA and everything including the EMP are gone.

SOUNDWAVE lets out a pulse that blows everyone to the ground, including OPTIMUS PRIME, and quickly rips Prime's chest open to unveil the MATRIX. He takes it and heads to MEGATRON. MEGATRON is given the MATRIX and the resurrection is now complete. MEGATRON turns his sights to STARSCREAM who needs a serious ass kicking.

Robot on robot action at it's best, jet on jet, MEGATRON vs. STARSCREAM. MEGATRON quickly defeats STARSCREAM and makes an example of him by dragging him through the streets by his wires and crucifying him for all to see all the while he narrates a call to STARSCREAM loyalists to come and avenge him and fight MEGATRON's army.

AUTOBOTS are on the retreat. STARSCREAM loyalists on CYBERTRON rocket off to fight MEGATRON on Earth and the DECEPTICONS surround the energy orb. Things are looking really bad.

SAM blames PRIME for MIKAELA's death and is shattered. Prime is being carried on ULTRA MAGNUS' trailer, alive, barely. HOT ROD, feeling to blame, heads back to the Stratosphere to see if there is anything salvageable. Luckily, when MIKAELA fell she fell on top of a DECEPTICON and his force field which saved her. As he dies and the field goes away, she wakes up and sees the destruction. The journey has just begun...