Mason is an idealistic legislative correspondent in Senator Abbott's office (VA) and recent Harvard grad. He lives with Pete Komisky, a lobbyist for an animal rights group and old friend from college. Mason's twin sister, Finley, comes to town running from graduate school. She begs to crash with Mason, but can't stand the bachelor pad, and so finds them a new place to move into... a beautiful town-house owned by family friends who are moving to Lithuania. With the new place, they have a guest apartment to rent out. Pete runs into an old high-school acquaintance, Sarah, who's looking for a place to live. Sarah, an investigative journalist, moves into the guest apartment with her boyfriend, Lewis, who clerks for the Supreme Court. Senator Abbott has an opportunity to become the new Chairman for Agriculture, and suddenly a project that Mason's working on regarding red ring-tailed squirrels becomes very important. Mason, with some help from Pete, finds an incredible solution to the squirrel problem, but his superior in the office, Neil, takes it out of his hands and screws everything up, leaving the senator looking very bad. Sarah alerts Mason to the problems, and Mason points them out to to Neil. Neil fires Mason, and Mason tries to save his pride by talking to the Senator before leaving with his tail between his legs.
When Pete and Mason apply for the same state department position, their friendship suffers. Luckily, Mason realizes that this job was always Pete's dream, not his, and even though Pete doesn't get the job, Mason looks elsewhere and ends up getting a job working for a representative from Ohio. Sarah asks Finely for help translating when interviewing a German diplomat about his many parking violations that he never has to pay due to his diplomatic immunity. Finley ends up going on a date with the German diplomat that turns out to be a job interview for the man's illegal car importing business. Finley tells Sarah, and they stay up all night researching the expose that helps Sarah make a name for herself at the network. Finely and Mason's parents are in town, and as usual Finley feels persecuted by them, but she is devastated when she accidentally finds out that her parents are separated and haven't told their children. Lewis is concerned with the unnofficial status of the apartment lease.
A smarmy neighbor tries to blackmail the gang, promising not to tell the Sorensons that five people are living in their house in exchange for $1000 a month. The gang turns the tables on the unfriendly doctor, taping him blackmailing them and blackmailing him back. Mason gets a chance to beat his old boss who fired him in a softball game and goes out on a promising date with Christy, who originally slept with Pete. Lewis's cousin, who is more or less his little brother, gets arrested for theft, which escalates to grand theft. Lewis puts his clerkship on the line to help defend his cousin, and advises the teen to turn on his bad influence friend. When his cousin finally agrees, the friend confronts him and Lewis's cousin ends up dead. Lewis can't help but feel responsible for the tragedy.
When a girl is brutally murdered by three classmates, Mason suggests to Congressman Owens that parental responsibility in such crimes is something he should take a stand on. Owens thinks it's a great idea, and has Mason start writing an ammendment while setting up a press conference with the dead girl's parents. Sarah leverages her relationship with Mason to get an exclusive interview with the parents, making herself look good to her network. Mason is upset when Sarah's questions lead the couple to admit that they don't really support parental responsibility. Mason's job is on the line, but he redeems himself by rewriting the ammendment for Owens with an eye toward not unfairly blaming good parents with bad kids. Meanwhile, Sarah is troubled that she lied to the parents and said that she had recently lost a cousin close to her to violent crime to get them to open up. Pete gets a new high-powered job more on the merit of his sexual charm than anything else. Finley gets a job at the Smithsonian after showing a tour guide up with her knowledge of and excitement about history.