Appearing in "Into the Abyss"
- Professor X (Charles Xavier)
- Legion (David Haller) (First appearance as Legion)
- Dr. Moira MacTaggert
- Ambassador Gabrielle Haller
- Multiple Man (Jamie Madrox)
- Jemail Karami (Psyche inside Legion's mind)
- Jack Wayne (First appearance) (One of Legion's personalities)
- Cyndi (One of Legion's personalities) (First appearance)
- Rogue (Referenced)
- Thomas Corsi (Referenced)
- Sharon Friedlander (Referenced)
- Sunspot (Bobby Da Costa) (Mentioned)
- Allah (Yahweh) (Invoked)
- Numerous unnamed people (All inside Legion's mind)
- Numerous unnamed demonic soldiers (All inside Legion's mind)
- Daniel Shomron (Mentioned)
- General Custer (Mentioned)
Races and Species:
- Heaven (Invoked)
- Legion's mind
- Numerous tanks, gunships, and jets (All inside Legion's mind)
- Korean War (Referenced)
Synopsis for "Into the Abyss"
Gabrielle Haller's son is sucking people's psyches into his mind, and Professor X is trying to figure out what is going on. Suddenly he is also drawn in as Sharon, Tom, Moira, and Wolfsbane were, along with Gabriell Haller, Mirage, and Cypher. David Haller's personalities identify themselves as Legion. Professor X and company gain access to David's mind, but not before he learns that Legion is his son.
They find themselves in a war zone that is a cross between Paris and the Middle East. Along the way, they meet Haller personalities Jack Wayne and Cyndi, and spy Jemail Karami from afar. Jack Wayne convinces Professor X that Jemail is the root of the problem, and Professor X resolves to go after him.