Sentinel Prime (Transformers Film Series)

"On Cyberton, we were gods. But here, they called us machines."

- Sentinel Prime

"I hereby discharge you from duty."

- Sentinel's quote when he killed Ironhide

"I bring you Cybertron, your home! And you still you choose humanity!"

- Sentinel Prime

Sentinel Prime is the main antagonist in the Live Action Movie; Transformers: Dark of the Moon. He can transform into a fire engine. Sentinel Prime was originally an Autobot, but betrayed the Autobots and sided with the Decepticons so he can save Cybertron. The movie's title Dark of the Moon is a reference to him and his space bridge pillar technology that forms the plot.

Sentinel Prime is known for being the only antagonist in the live-action Transformers franchise in which Optimus Prime would have never been able to defeat alone, even with his best efforts.

Past
On the Planet Cybertron, there was a great war that practically destroyed Cybertron. Sentinel Prime wanted to recreate Cybertron, so he made a deal with Megatron that if he was to side with the Decepticons, Megatron would help him recreate Cybertron. Megatron told him to take his Pillars (machines that can teleport anything) to the planet Earth and they'll recreate Cybertron there. Sentinel Prime flew away in a ship called the Ark that carried hundreds of Pillars. Sentinel warp jumped away from Cybertron but somehow accidently crashed landed on the dark side of the moon.

In 1969, Neil Armstrong was secretly assigned to search on the moon and anylizes the crash. Armstrong claimed there were no survivors. Since 1972 no one went to the moon since, and was deemed above classified. Neil Armstrong decided to take the space bridge pillars from the moon, which were then stored in secret by the government which became a law that no one is to know of the alien technology. This law was enforced by the arrogant Director of National Intelligence, Charlotte Mearing before Sentinel was revived.

Present Day
When Optimus Prime and Ratchet were helping their human allies, they encountered a piece of a machine that was originally part of the Ark. They flew to the dark side of the moon and found the Ark, with both Sentinel Prime, and five Pillars. With the Autobot Matrix of Leadership, Optimus revived Sentinel Prime. Sentinel took the form of a Rosenbauer Fire Engine. When Sentinel Prime and Optimus Prime were talking to each other alone, Optimus thought that since Sentinel Prime was his leader, Sentinel should have the Autobot Matrix of Leadership and lead the Autobots. However, Sentinel said that since he knows nothing about this planet, Optimus should keep the Matrix, teach him about the Planet, and continue being the leader of the Autobots.

Betraying the Autobots
The Decepticon sub-group trio, the Dreads (Hatchet, Crowbar, Crankcase) chased after Sentinel Prime. Bumblebee, Dino, Ironhide, and Sideswipe guarded Sentinel allowing him to escape while Ironhide and Bumblebee kill off the Dreads. After the chase scene ended Sentinel revealed his intention, claiming that the Autobots shall realize that Sentinel was not actually going to help the Autobots win the war, but instead turn against them and explained he made a deal with Megatron. In the process he murdered Ironhide with his Cosmic Rust Gun, and wiped out NEST, with only a few human survivors.

The Invasion and leading the Decpticons
With the help of Megatron, Starscream and other Decepticons, they were able to open a space gate so the Decepticons can invade Earth. He decided to spare Optimus, because he was his appentice once, and he wanted Optimus to watch the fall of the human race. They first took over Chicago and that if anyone tried to infiltrate they would be killed. The also killed most of the people who lived in Chicago (except of Dylan Gould and Carly). But during the invasion, Sentinel Prime attacked Megatron and told him that he's the true leader. He then took over the Decepticons as their leader. Similar to Optimus Prime, Megatron became betrayed by Sentinel. He bullied Megatron to leave so that Sentinel can gain full command of Decepticons, then soon the entire human race who he plans on enslaving to build Cybertron. Sentinel stayed out of most of the battle relying on the Decepticon warriors to carry out his plans, including Shockwave, Soundwave, Laserbeak, and Starscream.

Transporting Cybertron
Other Decepticons were placed around the world with a few of the Pillars. They were going to be used to open a Space Gate and bring Cybertron into the Earth's atmosphere. After the Red Pillar was deactivated by Optimus, (the Pillar that controls all the other pillars) Sentinel Prime fought all the Autobots and N.E.S.T. with little to no effort. While he was fighting the Autobots, Sentinel Prime told any surviving Decpticons to reactivate the Pillar. Turning the fight Sentinel attempted to retreat, but Optimus managed to catch up with him. Sentinel managed to cut off one of Optimus' arms was about to kill him. At the same time, Carly (Sam Witwicky's new Girlfriend) tries to convince Megatron to kill Sentinel Prime. She said that if Sentinel did succeeded in killing Optimus and transported Cybertron, Megatron would be nothing more than Sentinel's bitch. Convinced, Megatron rushed in, saved Optimus Prime, and stops Sentinel Prime by blasting him with the only weapon powerful enough to penetrate his strong hide and pulverizes him hard, claiming that Earth was his planet to conquer, only to be killed by Optimus Prime. Despite Sentinel begging for his life, Optimus grabbed Megatron's gun and executed Sentinel for betraying the autobot and human races over his awful obsession with Cybertron therefore stating that he "betrayed himself".

Comparisons to the Original
There is very little similarities from the G1 character and the film character. For instance, the G1 version was a hero. Even the movie characters design is different, but he does resemble another transformers character, Alpha Trion. But one thing is very similar; the characters personaity.

Transformers: Animated also had a character named Sentinel Prime. He was an Autobot in command of the Elite Guard, and was also an antagonist towards Optimus Prme, but not completely. Sentinel Prime was much similar in nature to Zapp Brannigan of Futurama fame as being an idiotic, selfish and rude leader who unfairly bossed around his cadets Jazz, Jetfire, and Jetstorm who are smarter than him. At the end of the series Optimus and his team captures Megatron and saved the universe leaving Sentinel jealous. However, live-action movie Sentinel Prime was far more evil and more aggressively hated by fans than in Animated. It turns out that the reason Animated Sentinel Prime hated Optimus was for leaving behind Autobot Elita One on a planet filled with giant spiders who he thought killed Elita. However, Animated Sentinel Prime forgave Optimus for this when realizing Elita One became a Decepticon after becoming infected with spider DNA to abandon the Autobots.

Trivia

 * Sentinel Prime is voiced by Mr. Spock himself; Leonard Nimoy, who also did the voice of Galvatron, in The Transformers: The Movie. Sentinel Prime even spoke, "The needs of the many outweigh the needs of the few", which was spoken by Leonard Nimoy's character Spock from Star Trek.