Alexis was born in March, 354 BC, in Pella. Her parents were Philos, Philip II's head blacksmith, and Scylla, a Macedonian woman of some status. She has one brother, Solon, born in 352 BC.
When Alexis was three years old she met Hephaistion for the first time. Her mother, Scylla, was bedridden for many months after Solon's birth, and Alexis was left in the care of the royal nurses, thanks to her father's status. She was four when she first met Alexander, who was two years her senior. She, Hephaistion and Alexander struck up an immediate and lifelong friendship and were hardly ever separated again.
At the age of eight, Alexis accompanies Alexander and Hephaistion, as well as some of the other boys, Cassander among them, to see Philip buying new horses. She trips Cassander when he taunts her about running slowly. It is clear already that they will never be friends. After Alexander has ridden Bucephalus, to the amazement of everyone present, Alexis convinces her father to purchase a horse for her, even though she is too young to ride.
When Alexis is ten, she is caught by Ptolemy watching the boys training. Alexander, Hephaistion, and Cassander are now twelve and have become pages and started training for the army, something Alexis wants to join more then anything in the world. Ptolemy agrees to give her lessons when he is not away on duty for Philip and when she is twelve, she is allowed to join the other boys training. After she begins training, Alexis teaches her brother Solon what she has been learning. Solon was born blind, but he displays an amazing ability to function as if he had no limitations.
During her fifteenth year, Alexis begins to realize that she and Hephaistion have developed feelings for each other. While exploring a cave together he finds a gold aulos necklace and gives it to her as a token of their friendship. A year later they share their first kiss, the same night as Philip's wedding to Eurydice. The wedding leads to a fight between Philip and Alexander and Alexander is banished. He flees north to Illyria with his mother, Alexis, Solon, Hephaistion, Ptolemy, Cassander, Niarcus, Perddicus, Leonnatus, and Menelaus, Ptolemy's younger brother. Alexis remains with them for only a few weeks before Philotas comes to retrieve her on the orders of her father. The story is given that her mother is ill and may die, however Philos embellished Scylla's illness in order to bring his children home safely. On her departure Alexander asks Alexis to spy on Philip for him.
Two years pass before the friends are reunited, with Alexander and the rest returning to Pella in March of 336 BC, the day Alexis turns eighteen. Five months later Philip is assassinated and Alexander becomes king, causing a great shift in everyone's lives, especially Alexis.
After the death of Alexander, Alexis becomes the de facto leader of the empire. Ptolemy returns to Egypt after the memorial and Alexis remains in Babylon to govern while Roxana, now the sole queen and pregnant with Alexander's heir, stays sequestered in her rooms.
Several months after Alexander dies, Cassander takes his mummified body and boards a ship to Macedonia. When Alexis finds out she immediately sends Kassos to Egypt, instructing Ptolemy, now recognized as Pharaoh, to intercept him. The Egyptian fleet takes Cassander's ships when they dock in Crete to resupply and Alexander's body is taken to Memphis, where work on a mausoleum has already begun.
Throughout the three years between 323 and 320 BC Alexis becomes known throughout Babylon for her charity work, handing out food and gold coins to the poor and many call her their Queen. Roxana remains sequestered with her son, the young Alexander IV, while Cassander plots to overthrow Alexis and take power for himself. During one of Ptolemy's rare visits to Babylon, Alexis confesses her fears and suspicions that Cassander was behind the deaths of both Hephaistion and Alexander. He shares her worry and both agree to take extra care in their everyday lives. In 321 Roxana demands that a new satrap be installed in Babylon, to do the job that Alexis has been doing for two years already. Alexis delays as long as she can, but between Roxana's ineptitude and Cassander's scheming, the people become unsettled and begin to riot. Alexis abandons Babylon and takes her troops, some ten thousand strong, across the desert and to Egypt, never to return.