Alex (born Alakay) is a lion and the main protagonist of the films. Alex is headstrong, protective and self-proclaimed leader of his friends. He is best friends with Marty (Zebra). He is used to the life of comfort in the zoo, but learns to adapt to the wild. He's smart, quick thinking and fast on his feet. He is a dancer by nature, often impressing others with his aerobatic feats. He does tend to be a little self-absorbed, often not seeing the problems of others above his own.
Alex enjoys his life at the zoo and has plenty of friends and is surprised when hearing Marty's wish to leave and live in the wild (Or run free in Connecticut as stated in the movie). As a cub, Alex was born on an African wildlife reserve and named Alakay. He has brown and yellow fur, whiskers, a black nose, a big mane, and a long tufted tail. He was the son of the alpha lion, Zuba, and was constantly given lessons on hunting, though he displayed no interest in the activity. During one of the sessions, Alex was captured by poachers, but the crate he was contained in fell into a river and eventually floated to New York. He is found by humans who renamed him Alex and took to the Central Park Zoo. In Madagascar, after Marty (Alex's best friend) leaves in an effort to take a train to the wild, Alex, Gloria, and Melman pursue him and are shot with tranquilizer darts by humans. The animal-rights activists pressure the zoo into releasing them back into the wild, but on the ship to the preserve, Alex and his friends fall into the ocean. They wash ashore on Madagascar, and, while Marty is excited to be free, Alex wishes to go home. He grows very hungry after days of being unable to eat, not realizing that steak is animal flesh. Hunger drives Alex into a crazed state, and after almost killing Marty in hunger (by biting him on the butt when he thought it was a piece of steak), in a moment of lucidity, he goes into self-imposed exile, barricading himself in the fossa territory of the island. Marty pursues him, unwilling to leave his friend, but is attacked by the fossa, the native predators of Madagascar. Alex works to defend Marty, and is later given sushi by the penguins to satiate his hunger.
In Madagascar: Escape 2 Africa, Alex encounters his parents, Zuba and Florrie, who are overjoyed to see their son and he becomes co-alpha lion alongside his father.
Zuba assumes Alex is strong after hearing he is the "king" of New York and arranges a rite of passage into the pride. Makunga, Zuba's rival, persuades Alex to challenge Teetsi during the Alex's rite of passage. Teetsi was revealed to be a bulky, strong lion and Alex is quickly defeated by him. To keep from banishing Alex, Zuba transfers his control to Makunga, and in turn, he, Florrie, and Alex are banished. Zuba soon grows unaccepting of Alex after realizing he is not a fierce warrior. The next day, the watering hole is shown to be dried up and Alex leaves with Marty to find out the cause. They leave the safety of the reserve, prompting Zuba to follow Alex and bring him back. Alex discovers that the stranded New Yorkers had created a dam, and through the use of dancing, he is recognized by the attacking New Yorkers. With the help of others, the dam is destroyed and they return to the preserve. His father learns to respect his habits, and they remain in Africa instead of flying home with the penguins. In The Penguins of Madagascar in a Christmas Caper, a stuffed animal Alex is seen briefly and its head is quickly dismembered by Nana's toy poodle, Mr. Chew. Alex has small cameos with his friends celebrating Christmas and singing a version of "Jingle Bells".
The fact that Alex loses the challenge to Teetsi and is spanked by Nana in Madagascar gives him the impression he is a horrible fighter, but this is not true, because (in the Nana case), she only gets Alex by surprise, but was more visible when in Madagascar 2, he has a short, but equilibrated[clarification needed] fight against Nana. Alex is shown to have a superhuman level of interior physical strength, seeing that he broke the zoo's public telephone, and lifts Melman, Marty and Gloria with relative ease.
Alex made another appearance in "The Return of the Revenge of Dr. Blowhole." Wally Wingert reprises his role from the video games. In the show, he appeared as a hallucination "spirit guide" to help Skipper, whose memories had been stolen by the evil Dr. Blowhole. At first, Skipper thought he was very talkative and annoying, but soon he accepted his guidance, especially when he had to face Blowhole when he got back to New York City. A running gag in the episode is that Skipper's friends are confused and convinced he's crazy when they see him talk to Alex, since only Skipper can see him. After Dr. Blowhole was defeated, Alex's spirit guide form disappeared.
In Madagascar 3: Europe's Most Wanted, it opens on Alex's birthday and after a present from his friends of a mud New York he is determined to get the penguins from Monte Carlo. Alex creates four phases and after a fight with his friends they are exposed and are pursued by Captain Chantel DuBois.
After cutting the DuBois' snare they fly back to New York until they crash in a trainyard. Alex is determined to get back home and tries to fix the plane but fails. Then he persuades Gia to let them on the train, with whom he is smitten upon first sight. After being let on the train Alex and the gang realized that this was a ticket home.
After a failing performance in Rome he gives a pep talk and has the circus spiced up to get the circus promoter for a tour in America. Stefano told Alex why Vitaly was grouchy. Alex teaches Gia trapeze, and they begin to fall deeply in love. The London performance was better and they go to America. DuBois came to "take home" Alex but gets shot out of a cannon. Alex tells them why they had to join the circus.
Alex gives another pep talk to his friends and Julien that they were wrong and they decide to go back until DuBois comes. Awakening, Alex realizes they are back in the zoo with iron cage links between them. Luckily the circus came and rescued him. But DuBois is still determined to get Alex's head and is taking Stefano. But Alex saves the day (with Gia's help) by saving Stefano and defeating DuBois.