Petra Martínez Petra Martínez is a Spanish actress who played Petri in the Spanish " Sesame Street " co - production " Barrio Sésamo " . Martínez began her career in Spanish cinema in 1976 , with awarded movie " And They Lived Happily Ever After . " She then went to a small role as a bookseller in Manuel Gutiérrez Aragón ' s " Black Litter " ( 1977 ) , a movie which was awarded in the Berlin International Film Festival . From 1979 to 1980 , Martínez worked on the first period of " Barrio Sésamo " . She played one of the adult human characters . However , she could not renew her contract for the second season of this first period , and thus Petri simply disappeared from the Barrio , apparently with nobody missing her . Martínez then disappeared from the screen for no less than fifteen years . She suddenly came back with internationally - awarded movie " Entre Rojas " ( 1995 ) , directed by Azucena Rodríguez and starring Almodóvar - favorite Penélope Cruz . Since then , she has continued working with other Spanish stars , such as Eduardo Noriega in short feature " Allanamiento de morada " ( Mateo Gil , 1998 ) , where she played a missing person , and " Nobody Knows Anybody " ( again Mateo Gil , 1999 ) , where she played one of the characters providing important clues to Noriega ' s . Both of the movies won widespread recognition and awards , although Martínez ' s participation did not . However , her career was increasingly growing for a mature actress . She acted in short " Frasquito " and in Pedro Teleche ' as " El invierno de las anjanas " in 2000 . During 2001 , Martínez had a chance to act in different movies , including Jorge Iglesias ' comedy " Fish People " ( where she makes a cameo at the park , next to Fernando Chinarro ) , and award - winning dramas " Savages " ( Carlos Molinero ) and " Mine Alone " ( Sergi López , the movie that definitively launched Paz Vega ' s career ) . She also , for the first time in her career , had a chance to play the top bill on a movie , in Antonio Muñoz de Mesa ' s short , " El Diskette " . As a rest , she only appeared as a guest in TV series for all 2002 , but they were popular TV series : " Hospital Central " and " Policías , en el corazón de la calle " . 2003 would mean a big - time return after her holiday . She appeared as a recurrent guest star for TV series " Código fuego " and played the mother of star Óscar Janeada in Achero Mañas ' " November " . She also was top - billed in Xavi Sala ' s short " 60 years old " , and co - top - billed with Manuel de Blas in Gaizka Urresti ' s dramatic short " Raíz " . In 2004 , she played in three movies , in almost of the genres an actor could hope for . Firstly and most recognized , she was the mother in Pedro Almodóvar ' s super - production , " Bad Education " . She also appeared in Daniel Múgicas ' thriller " Matar al ángel " , and played an unhappily - married woman in Javier Balaguer ' s comedy " Escuela de Seducción " , starring Victoria Abril , Javier Veiga , and José Manuel Cervino as Martínez ' s husband . Now a veteran actress , she usually shares a set with some of the most recognized actors in Spain , such as Rafael Álvarez ' El Brujo ' in recent " Angosto " ( 2006 ) . Martínez is still working now , and her last release was Javier Rebollo ' s " Locos por el sexo " ( 2006 ) .