At age seven, Martin appeared in the
Broadway National Tour of
The Sound of Music with
Richard Chamberlain. Two years later she portrayed young Cosette in the Broadway National Tour of
Les Miserables. She appeared on Broadway in the title role in
A Day in the Death of Joe Egg at the age of 10; her acclaimed performance gave her the opportunity to be the youngest presenter in history at the 2003
Tony Awards.
The New York Times profiled her when she was 12 years old. She appeared onstage in
The Pillowman alongside
Jeff Goldblum and
Billy Crudup. She acted in
A Christmas Carol at Madison Square Garden. Her first appearance on television came in 2003 on
Law & Order, where she played the role of Annie for one episode. Also in 2003, she did the voice acting for the main character JoJo, in the cartoon TV series ''
JoJo's Circus''. She was a series regular on Disney's
Out of the Box. She was called back in 2004 for another episode ("Sick"), on
Law & Order: Special Victims Unit, as April. In 2005, she appeared for one episode on another TV series,
Hope & Faith, as Ivana Charles. She is also known for appearing in several commercials, most notably for
Staples (2004) and
Ford Escape Hybrid (2007). In 2006, Martin was a voice actress in
Ice Age: The Meltdown, where she voiced several roles. She returned to TV in 2007 to act alongside
David Duchovny in the
Showtime dramedy
Californication as Becca Moody, Duchovny's character's teenage daughter. She performed several songs in
Californication including "
Only Women Bleed", "
Don't Let Us Get Sick", and "
Surrender". Martin originated the role of "Jean Fordham" on Broadway in the hit play
August: Osage County. In 2010, she was a co-star alongside John Cena in the
WWE Studios film,
Legendary. Her performance was heavily criticized. She voiced Finn's female counterpart,
Fionna, in the
Adventure Time episodes "
Fionna and Cake", "
Bad Little Boy", "The Prince Who Wanted Everything", "Five Short Tables" and "Fionna and Cake and Fionna"— and voiced the character in the spin-off series
Adventure Time: Fionna and Cake. She also appeared in the
Criminal Minds Season 7 episode "Heathridge Manor". Martin performed in the Atlantic Theater Company's production of
Harper Regan in 2012 and on Broadway in
Picnic in 2013. From 2014 to 2016, she played Shelley Godfrey in the second and third seasons of
Hemlock Grove and had a guest role on
The Good Wife. She performed in the
Lincoln Center production of
The Harvest in the winter of 2016. In 2019, she portrayed Madeline in
The Marvelous Mrs. Maisel, a recurring character in the third season. The character is a colleague of Abe's (the titular character's father) in his fight in rebellious causes. Outside of acting, Martin is also an assistant professor at
Florida State University. ==Filmography==