It wasn't that long! Cliffhanger at the end of Brotherhood, you forgot to put. ha ha ha. The Roman Gods, they are. They say they are just an advanced civilization.
Here is a few of my discriptions.
WARNING: May contain spoilers!
Altair has betrayed the creed, and must regain his "honour" by killing Templars, (was it 8 or 9 of them?) [8 or 9] lives for his to be back up top of the brotherhood.
Ezio's 1 Story
Betrayal, Blood, Death
A conspiricy, murders, all for power.
Ezio must learn the ways of the Assassins, and become the master Assassin to find (a) Pieces of Eden (staff and apple). Rodrigo Borgia, the pope, is the leader of the Templars at this time.
Ezio's 2 Story
Ezio is now older and more mature. He must adventure to Rome and fight the Templar threat. Ceasar Borgia, son of Rodrigo, is the new man in power, the new leader.
Desmond, a bartender, has been kidnapped by Abstergo Industries, a company that has most modern day discoveries; cars, medicine, NASA, ect.; has need of him and his Assassin ancestory and family. He must relive Altair's life and find a map to the pieces of Eden for the Templars, Abstergo Industries is just a front name for them. Lucy, a worker, he thinks is on his side, helps him escape the company and Waren Vidic (a boss of Abstergo Research).
They escape to a hideout where they mean Shawn and Rebecca. Desmond must learn to become an Assassin, he was to be one before he ran away from his home, and stop the Templars. He relives Ezio's life, as he learns moves and skills and powers from the previous Altair and the new Ezio. He has only a few days to learn this. Soon Vidic comes and makes them on the run again. He gains "THE HIDDEN BLADE"!
They go to the ville, that Ezio once lived with his uncle, the Audutoire Ville, Montaggria (SP). They now have him finding where Ezio's PoE (Piece of Eden) is, where he put it, hidden it from the Templars. He is allowed to explore a bit more around the ville to get "exersise". They soon go to Roma. They go to the Colloseum, and have Desmond explore the ruins of it. They find "church" thing, built upon the Temple of Juno and the vault. They find the Apple of Eden and when Desmond picks it up, his "DNA" activates it. Juno takes control of him, and throws Desmond into shock, killing Lucy.