These are the two actors the show will depend on. One fairly fresh faced and new, the other experienced with an established following. Their interactions are some of the best parts of the episode, and there will definitely be a power struggle between the two as the series goes on. Cameron initially wants out, but by the end of the pilot, decides to stay. However, I do not see him going along easily with Oz's free-wheeling ways, so there are bound to be plenty of clashes.
Joining Cameron and Oz in this odd job are Cash (Alphonso McAuley), a nerd obsessed with candy bars and hazing the new guy in outrageous ways, Josh (Trevor Moore, The Whitest Kids U'Know), a sometimes jerk and flaw(less?) character actor who vies for leadership, Creepy Carol (Jennifer Irwin, Eastbound & Down, Still Standing), an annoying office worker who sneaks up on people, and Melanie (Odette Annable, formerly Odette Yustman, October Road, Brothers & Sisters, Cloverfield), a total psycho whom Cameron is attracted to. Of course, she already has a boyfriend, with a personality more similar to hers, named Dutch (Smallville's Lex Luthor, Michael Rosenbaum). There are other employees; it's a big office; but none that got any attention or lines.
Rosenbaum will make you forget all about Lex in seconds. He is unrecognizable with hair and an attitude. Moore basically takes all of the things he does well in his IFC sketch show and does them within a larger plot, a good use for the actor. Irwin is likely a recurring character, but her familiar face is welcome. McAuley is funny, and I assume Cash will be Cameron's best friend before long. Annable is everything you want in a love interest. She's generically sweet and attractive, but it's the flashes of insanity that will set her apart. Ensemble wise, the chemistry is great from the get go. Each different personality brings something unique to the table, which will help with varied assignments.