fakes a speech impediment as a defense mechanism. Dianna Agron plays Quinn Fabray, Finn's cheerleader girlfriend, who later joins the glee club to keep an eye on him. Mark Salling plays Noah "Puck" Puckerman, a good friend of Finn's on the football team who at first disapproves of Finn joining the glee club, but later joins it himself. Naya Rivera and Heather Morris portray Cheerios and glee club vocalists Santana Lopez and Brittany Pierce respectively and were originally recurring actors, but were promoted to series regulars in the second season. Mike O'Malley, who plays Kurt's father Burt Hummel, also became a series regular on season two. Gilsig and O'Malley no longer appeared on the list of starring actors at the beginning of the third season, though O'Malley was a recurring guest star in at least six episodes during the season. Two actors were promoted to series regulars as of the third season: Harry Shum Jr. as football player and glee club member Mike Chang and Darren Criss as former Dalton Academy Warbler and new club member Blaine Anderson, both of whom started as recurring actors, Shum in the first season and Criss in the second. For the fourth season, Chord Overstreet, who started as a recurring actor in the second season, playing glee club member Sam Evans, was promoted to the main cast, while Agron and Mays were credited as recurring guest stars. Many of the original characters graduated from McKinley High at the end of the third season. Murphy said, "We didn't want to have a show where they were in high school for eight years. We really wanted to be true to that experience." Adult characters played by Matthew Morrison and Jane Lynch would remain to provide continuity to the series, though according to Falchuk, some students—Rachel, Finn and Kurt in particular—would likely remain on the show after they graduate. In May 2012, Murphy said that just because a character on the show graduates high school does not mean that they are leaving, "A lot of people have been writing Dianna's off the show, Amber's off the show — they're not off the show. I think Amber was talking about that bittersweet feeling of, 'I'll never be in the choir room with that exact group of people.' At least that's what she told me ... When I read that [tweet,] I said, 'I think people will misconstrue that.'