Cas Russell

original cover of Zero Sum Game created by Najla Qamber

Cas Russell is crazy good at math. She can calculate vectors and probabilities to get her out of almost any hot spot, but in between jobs it overwhelms her, showing her the mathematics of every aspect of anything she looks at and every movement she makes. Her one steady friend-not-friend is Rio, but lately she's been learning that she can have other friends as well. She's also beginning to learn some unsettling things about her past and why she might have these uncanny calculation skills in the first place.

## History

This is a mystery slowly revealed over the course of the series.

## Friends & Associates

At the beginning of *Zero Sum Game*, Cas doesn't have any friends. The closest thing she has to a friend is Rio. Over the course of the series she begins to fumble her way through having real friendships.

### Not-Friend

#### Rio

Rio fulfills all the requirements of friendship except for actually caring about her.

### Friends

This is new for Cas. She isn't very good at it.

#### Checker

Checker drinks with her in between jobs, and made her watch the *Star Wars Holiday Special*, for which she will never forgive him. She figures she shouldn't let him get killed, though.

#### Arthur

Cas has this weird desire to keep Arthur from dying. He also has this annoying habit of being her conscience.

#### Pilar

Cas offers to shoot people for Pilar and Pilar breaks into Cas's apartment to clean up vomit. That makes them friends, right?

#### Sonya

They work well together on math, but their personalities are different to say the least, and Sonya reminds Cas of a painful hole in her life.

### Reluctant Allies

These people are usually unfriendly towards Cas, and she towards them.

#### Unnamed Anti-Pithica Organization

This includes the persons known as Steve and Finch.

#### The Lorenzos

After they stop trying to kill her, before they start trying to stop all her business.

#### Agent Jones

Might be classifiable as an antagonist as well.

## Antagonists

Antagonists are not always enemies, and sometimes the biggest problem is Cas herself.

### Organizations

Pithica

They want to make the world a better place.

#### DHS

Also sort of an ally, at different points.

### People

#### Jacob Poudry

Human trafficker and piece of shit in the first degree.

### Other

At the end of *Zero Sum Game*, Dawna rips through some careful telepathic word in Cas's mind. As the series unfolds, Cas begins to have more and more problems with her brain.

## Jobs

Retrieval jobs that Cas is hired for or agrees to do.

* Courtney Polk
* Courtney Polk's US life
* Samples for Harrington
* Liliana
* Gemstones
* Math proof and thief, and creator
* Trafficked children

Non-retrieval jobs that Cas is roped into doing by herself, friends, or clients:

* Stop Pithica
* Murder rehab
* Help Checker with Mama Lorenzo
* Quell robot and anti-robot violence
* Be a better person
* Take down Poudry
* Stop widespread crime in LA

## Multi-Book Story Arcs

### Pithica

This starts in *Zero Sum Game* and continues in *Null Set*, although the presence is felt throughout the intervening books.

### Cas Russell's Past

At first she doesn't realize it's normal for other people to have one. This arc includes the role of Rio in her life.