journalism and becomes a local news anchor. Michael Welch as Luke Girardi, the youngest Girardi child. Luke is a science nerd and straight-A student. He has a brief romantic relationship with Glynis Figliola and later begins a relationship with Grace Polk. Chris Marquette as Adam Rove (Recurring Season 1; Regular Season 2), Joan's best friend and later boyfriend. Adam is the only child of Elizabeth (deceased) and Carl Rove. Adam is socially awkward and introverted but is also a talented artist and one of Helen's art students. Becky Wahlstrom as Grace Polk (Recurring Season 1; Regular Season 2), Adam and Joan's best friend and Luke's eventual girlfriend. The only child of Sarah and Rabbi Polanski, Grace is outspoken against all authority, with a particular distaste for school vice principal Gavin Price. She is highly intelligent despite her rebellious reputation. After years of putting it off, Grace finally has her bat mitzvah in "The Book of Questions". Recurring cast David Burke as Father Ken Mallory, Helen's friend and pastor of a nearby church. Haylie Duff as Stevie Marx Patrick Fabian as Gavin Price, the vice principal of Arcadia High School who is unpopular among students. John Getz as District Attorney Gabe Fellowes, a corrupt public servant who is arrested during an investigation of corruption into the Arcadia city government. April Grace as Detective Toni Williams, as Will Girardi's partner on the Arcadia Police Department and later the Hogan County Sheriff's Department in season 1. Sprague Grayden as Judith Montgomery, Joan's friend from the summer psychiatric camp. Elaine Hendrix as Ms. Lischak, chemistry and physics teacher. Aaron Himelstein as Friedman, Luke's best friend. Wentworth Miller as Ryan Hunter, a young, charming dot com millionaire who also talks to God, but with his own sinister agenda. Derek Morgan as Hogan County Undersheriff Roy Roebuck. He previously served as head of the Arcadia Police Department Internal Affairs Division before being forced to transfer to the Arcadia Fire Department as the arson investigator. After the dissolution of the Arcadia city government, Roy became the Commanding Officer of the Hogan County Sheriff's Department Arcadia Station. He resigns after learning that two of his officers were corrupt and had murdered a witness. Erik Palladino as Lt. Michael Daghlian, the senior detective of the Arcadia PD under Chief Will Girardi. He is fired after removing evidence from an official report. Sydney Tamiia Poitier as Rebecca Askew, a reporter