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"I control Web Access America. I know the identity of all the screen names. The chat room is full of different types: people who are actually Controllers, trying to throw suspicious humans offtrack; humans who have discovered our little invasion and are trying to rally opposition to us; and then, there's me. I spot the Controllers. I spot the humans who think they have found family members who are Yeerks. I monitor the real gung-ho Yeerk-fighters who identify potential Controllers. I track down the screen names. I find the Yeerks. One every three days. Ten a month."
―Esplin 9466 Lesser[src]

Esplin 9466 Lesser was a Yeerk and the younger twin brother of Esplin 9466 Prime, better known as Visser Three.


Hork-Bajir Conquerors

"I was standing by the edge of the pool, joking with my twin. Yes, of course, I am a twin. But I am the primary. He is the secondary. We were talking about tactics for fighting with Hork-Bajir blades when we heard the cries."
Esplin 9466[src]

Esplin 9466 Lesser was present during the invasion of the Hork-Bajir homeworld in 1968, in possession of a Hork-Bajir host body and discussing battle tactics while joking around with his elder twin brother, Esplin 9466 Prime.

A New Life

"When there are twins, one is considered the prime, and one the lesser. I am the lesser. My brother, my twin, is the prime. To him go the best assignments, the best hosts, the rank, the power, the glory. And to me, only what I can take."
―Esplin 9466 Lesser[src]

When a pair of Yeerk twins are born, it is usual for the eldest, dubbed "Prime", to become a success and gain power and influence, while the other – designated "Lesser" – is left with nothing. While it is possible for twins to share power, this very rarely happens. Over the years, Esplin 9466 became ambitious and power hungry, and intentionally assigned his younger twin the host of a lowly programmer named Joe Bob Fenestre, who worked in the bowels of a telephone company. Esplin 9466 Lesser decided to turn his misfortune around. Using Fenestre's knowledge of human businesses, and his own knowledge of advanced computer systems, he created Web Access America, which quickly became the world's leading Internet Service Provider. The success of the company made Fenestre a billionaire and household name, and gave Esplin a vast information network - not only the names and addresses of WAA's subscribers, but more personal information gleaned from e-mails and chat rooms. Esplin quickly gains influence in human society, making him an asset to the Yeerk invasion.

However, Visser Three, fearing his brother's rising popularity and ambition, declared him a traitor, forcing him into hiding. Fenestre built a huge mansion and guarded it heavily. Knowing that his twin's host had the ability to morph into animals of all sorts, he equipped his mansion with weapons, ranging from Rottweliers and guards with submachine guns to insecticides and electrical force fields. His guards had instructions to shoot anything that attempted to come close to the house.

The Animorphs became suspicious of Joe Bob Fenestre when they infiltrated the Web Access America offices, looking for the names and addresses of users in a chat room whom they believed were in danger of Yeerk infestation. They discovered that Fenestre had been a participant in the same chat room, with the username "Fitey777", and decided to investigate Fenestre's mansion.

Although the mansion's security was difficult to break through, they were eventually able to gain access and meet with Fenestre - and Esplin. Esplin explained to the Animorphs that the only reason that he was still alive was due to a technique he had discovered that let him substitute a powder made from the bodies of Yeerks for Kandrona rays, sustaining his life without needing to visit the Yeerk pool, but forcing him to become a cannibal. He presumed that Visser Three allowed him to live only because he desired Esplin's technique; but, as he explains, the technique would never catch on in Yeerk society.

After Esplin had told his story, Cassie, horrified by his cold-blooded attitude towards humans and Yeerks, demanded that Jake kill Esplin. Jake, however, had already agreed not to harm him, but as a compromise, adds a condition: Esplin may never leave his mansion again. Esplin agrees; however, a few days afterwards, Fenestre's house burns down under mysterious circumstances. It is implied, but never stated, that Jake or Cassie may have done this. Nobody died in the fire, but Esplin's fate was never discovered.[2]



  1. At the end of #16, his house is set ablaze. While the Yeerk is presumed deceased as they do not resurface, officially their fate is left unknown.
  2. The Warning