Jodi Lyn O'Keefe (born October 10, 1978   ) is an American actress and model, who at age 17 began portraying Cassidy Bridges on Nash Bridges . She is also known for her role on Prison Break as Gretchen Morgan, a.k.a. "Susan B. Anthony", and as Josette "Jo" Laughlin in The Vampire Diaries .
O'Keefe was born in Cliffwood Beach, New Jersey,  the daughter of Noreen, a homemaker, and Jack O'Keefe, a director of labor relations for Merck.  She has Czech, Irish, Polish, Swedish and Austrian ancestry. O'Keefe has two older sisters, Jenna and Heather.
O'Keefe started her career as a model at the age of 8 years old, and she did some modeling work for a Jeans company. Midway through her junior year of high school, O'Keefe left school to star on the soap opera Another World , playing Marguerite “Maggie” Cory. She then got a role on Nash Bridges playing Cassidy, the daughter of Don Johnson ’s title character.  She and her mother moved to Hollywood so O'Keefe completed her schooling by mail.
O'Keefe made her big screen debut in 1998 in Halloween H20: 20 Years Later   and later starred in such films as The Crow: Salvation ,  Whatever It Takes  and Devil In The Flesh 2 .  In 1999, she co-starred in the teen film She's All That (1999) as Taylor Vaughan alongside Freddie Prinze Jr. and Rachael Leigh Cook.   When asked if it was hard to play her character, a high school prima donna, she replied, “Everybody knew a Taylor Vaughan in high school. Working in show business, you meet girls like that every day.”
O'Keefe kept on filming both movies and Nash Bridges until the series ended in 2001. Later films have included Out for Blood , in which she played a vampire named Layla Simmons and Venice Underground . On the small screen, she has appeared in various shows including Dharma & Greg , Boston Legal , Two and a Half Men , Charmed , The Evidence ,  The Big Bang Theory , and Tru Calling .
In 2007, O'Keefe was cast in a starring role on the series Prison Break ;  she was a part of the show's cast through its third and fourth seasons. O'Keefe has said that she "truly loved" playing the part of her Prison Break character Gretchen Morgan, because it "challenged" her, and because Gretchen was the "polar opposite of her" and "was badass". 
In 2014 O'Keefe was cast in a recurring role in VH1's TV series Hit the Floor ,  and appeared in the film Merry ExMas . The same year, she was also cast in the recurring role of Jo in the sixth season of The CW series The Vampire Diaries . 
In 2009 she appeared in the stand-alone add-on of the video game Command & Conquer: Red Alert 3: Uprising .
In June 2013, O'Keefe did a photoshoot for NOH8 campaign.
On June 22, 2011, O'Keefe started her own clothing line, Queen George Clothing.
In 2012, O'Keefe launched her own jewelry line, Q.
O'Keefe is also a licensed bounty hunter together with her friend Victoria Pratt, with whom she starred in the movie A Nanny's Revenge .
|1998||Halloween H20: 20 Years Later||Sarah Wainthrope||Film debut|
|1999||She's All That||Taylor Vaughan|
|2000||The Crow: Salvation||Lauren Randall|
|2000||Whatever it Takes||Ashley Grant|
|2000||Devil in the Flesh 2||Debbie Strand / Tracy Carley||aka. Teacher's Pet |
|2002||Falling in Love in Pongo Ponga||Shawnee||Short film|
|2003||Red Rover||Kylie Logan|
|2004||Out for Blood||Layla Simmons||aka. Vampires: Out for Blood|
|2004||Mummy an' the Armadillo||Jackie|
|2007||American Identity||Lyndsey Simpson||Short film|
|2013||Frozen Ground||Chelle Ringell|||
|2014||Merry ExMas||Ashley Williams|
|1995||Another World||Maggie Cory #4||6 episodes|
|1996–2001||Nash Bridges||Cassidy Bridges||Main role, 76 episodes|
|1999||Happy Hour||Herself||1 episode |
|2002||Dharma & Greg||Simone||Episodes: " She's with the Band ", " Mission: Implausible "|
|2002||George Lopez||Campbell||Episodes: " Who's Your Daddy? ", " The Wedding Dance "|
|2003||The Pool at Maddy Breaker's||Maddy Breaker||Television movie|
|2004||Tru Calling||Candace Aimes||Episode: " Reunion "|
|2004||The Help||Becky Wiggins||Episode: "Maggie Chicken"|
|2004||Charmed||Spider Demon||Episode: " Spin City "|
|2004–2005||Boston Legal||Nora Jacobs||4 episodes|
|2004||Two and a Half Men||Gail||Episode: " Last Chance to See Those Tattoos "|
|2005||Eve||Rita's stepmother||Episode: " If the Shrew Fits "|
|2005, 2010–2011||Two and a Half Men||Isabella||3 episodes|
|2005||Adopted||Rachel Rabinowitz||Television movie|
|2005||Three Wise Guys||Mary Ann Davidson||Television movie|
|2006||Halloween: 25 Years of Terror||Herself||1 episode|
|2006||The Evidence||Officer Jackie Kazaris||Recurring role, 5 episodes|
|2006||Criminal Minds||Agt. Amanda Gilroy||Episode: " P911 "|
|2006||The 12th Man||Lindsay||Television movie|
|2007||CSI: NY||Melodee Constanza||Episode: " The Ride In "|
|2007||Raines||Angelina Billings||Episode: "Closure"|
|2007||The Call||Jenna "Kinky" Kincaid||Unsold television pilot |
|2007–2009||Prison Break||Gretchen Morgan||Main role (seasons 3–4), 32 episodes|
|2009||The Big Bang Theory||Mikayla the Prostitute||Episode: " The Vegas Renormalization "|
|2009||Prison Break: The Final Break||Gretchen Morgan||Television movie|
|2010||Lost||Ava||Episode: " Recon "|
|2010||Soul Fire Rising||Lilith Reborn||3 episodes|
|2010||Class||Kylie Burch||Television movie|
|2011||Law & Order: LA||Jenn Mackie||Episode: "Angel's Knoll"|
|2011||Exposed||Emily Bennett||Television movie |
|2012||The Finder||Lisa / Mandy||Episode: "A Cinderella Story"|
|2012||Castle||Kristina Coterra||Episode: " Cloudy with a Chance of Murder "|
|2012||A Nanny's Revenge||Gina Wright||Television movie|
|2013||The Exes||Employee||Episode: " Toy Story "|
|2013||Stalkers||Julia Winston||Television movie; aka. Whisper of Fear (based on the book of the same name)  |
|2014||Untitled Wall Street Project||Riley Simms||Unsold television pilot |
|2014–2015, 2017||The Vampire Diaries||Josette "Jo" Laughlin||Recurring role (seasons 6–7); guest role (season 8); 22 episodes|
|2014–present||Hit The Floor||Lionel Davenport||Main role, 24 episodes|
|2016||Lucifer||Ronnie Hillman||Episode: " The Would-Be Prince of Darkness "|
|2009||Command & Conquer: Red Alert 3: Uprising||Kelly Weaver|