Transformers: Age of Extinction went on to become a huge box-office success but the fate of Transformers 5 is still unknown as director Michael Bay has already hinted his exit from the fan favourite franchise.

But this has not stopped fans from speculating about the plot of the upcoming movie and many websites are brainstorming about how the movie will move forward.

Initially, there were reports that Optimus Prime will venture into space in order to settle scores with the Creators in the second movie of the latest trilogy of the live action thriller.

In the meantime, Rodimus Prime will take the responsibility of humans on earth, safeguarding them from Galvatron and his army of Decepticons.

However, Christian Post suspects that the Autobots will expand their reach by adding more of the Transformers including Ultra Magnus, Red Alert and Override.

The Decepticons too will become stronger as Cyclonus, Scourge and Blitzwing will be joining them.

This is not all, the Quintessons will descend on Earth to join the battle. There are also reports that the movie will introduce Rodimus Prime, Vector Prime and Unicron.

Enstarz suspects that Opimus Prime might guide the Creators to earth in order to join their fight and help them win against the Decepticons.

The Transformers 4 ended with Optimus Prime heading off into space to meet the Creators and seek answers from them about the events that happened in Extinction. He also takes the destroyer 'seed' along with him.

According to the website, another possibility is that the leader of the Autobots may not return to earth and in his absence Ultra Magnus will take charge with Cyclonus emerging as the main antagonist instead of Galvatrone.

The report also suspects that Vector Prime and Rodimus Prime will join the good transformers while Red Alert and Scourge will fight along with Cyclonus.

Amid speculations, one bitter fact remains: The lead star of Transformers 4 Michael Wahlberg is not returning for the rest of the trilogy. However, Megan Fox may return to the fifth instalment of the popular movie franchise.

The movie is expected to be released in 2016.