For her first regular role, Shantel VanSanten has done rather well for herself.

The unknown actress, who has appeared on an episode of CSI: NY, has joined the cast of One Tree Hill.

Sources confirm to Michael Ausiello that the relative newcomer has landed the key new role of Quinn, one of Haley's older sisters. Look for the character to show up this fall with a damaged heart, in search of someone to mend it.

VanSanten joins Robert Buckley as a new addition to the One Tree Hill cast.

In other casting news: Danneel Harris will return as Rachel for at least one storyline next season.

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.