|Voice By||Katie Leigh (Seasons 1 & 2)
Katie Griffin (All other appearances)
Alexandra "Alex" has short black hair, tan skin, and brown eyes, and appears to be half-Hispanic (she is the only main character whose father was seen in the show, but her father was white rather than Hispanic as her mother was), though has a taste for Chinese outfits, often seen wearing a Chinese dress to formal occasions. Her spy catsuit is golden-yellow. She is an odd mixture of a tomboy and a girly girl, in that she has more of an interest in sports and athletics but also shares her friends' fashion interests sometimes even to the same extremes as Clover. Alex is also the most naive and absent-minded. She sometimes is bit slow to some of the figures of speeches and takes them too literally. She also has a bit of a confidence problem, often comparing herself to her friends and thinking she isn't as interesting or pretty as they are. She is also very selfless— for example, in "The Show Must Go On...Or Else", she pushes Clover out of the way of a ray, ultimately transforming her but saving Clover.
Though their exact ages are never given, Alex is officially stated to be the youngest of the spies, though all three are in the same grade. In some ways, she can also be seen as the most childish of the girls— for example, her oldest and dearest friend is a toy turtle named Ollie, she has a turtle backpack, and she doesn't eat anything "cute". She also loves animals, In Totally Spies! The Movie Alex adopts a pig that she names Oinky, and in "evil mascot", Alex can be seen cuddling a kitten that hates the silent siren and eventually loves alex, especially when the kitten is taken to W.O.O.A.P.-the World Organization Of Animal Protection. Although Alex has been captured the least during the series, running gags in the series involve her often bad luck, clumsiness and poor driving skills. Alex also loves the color pink.