Moussier had a quiet childhood in Mexico City, where as a teenager she took an interest in acting and attended Televisa's Centro de Educación Artística.

[citation needed] In 2001, Moussier joined the cast of El derecho de nacer (a remake of the 1981 telenovela) as Graciela, a seemingly demure secretary who, disguised as a nun, frequents Yucatec brothels in order to satisfy not only her clients' base desires, but her own as well.

In February 2005, Moussier starred as Évora's ex-fiancée in La madrastra as the vain and haughty murder suspect Fabiola de Mendizábal, a character with hints of mental instability who nonetheless redeems herself by the novela's end and winds up happy with her equally suspicious husband, Bruno (René Casados).

Three months later, she debuted in Piel de otoño as ambitious businesswoman Rebeca Franco, who carries on an affair with the heroine's villainous husband Ramón (Sergio Goyri).

[3] After giving birth to her second child, she returned to telenovelas late in 2006 as mafia boss Eva Santoro in Amar sin límites.

She briefly reunited with the cast of La madrastra and took up the role of Fabiola in order to re-film the final ten episodes of the telenovela, which was being re-aired at the time, and to provide a new resolution to the murder mystery.

She joined the star-studded cast of the mini-novela Amor sin maquillaje as Beatriz, pairing up with Piel de otoño co-star Sergio Goyri.

[4] Marissa becomes a more sympathetic character after it is revealed that she was forced to have an unwanted abortion at the age of 15 and after her fiancé Santiago (Jaime Camil) leaves her pregnant at the altar for her friend, Candy (Jacqueline Bracamontes).

Though she and producer Juan Osorio Ortiz initially altered her filming schedule in order to accommodate her recovery, she was forced to withdraw from the cast shortly before the finale.

In 2015, Moussier starred as the main antagonist Macaria, a seductive, hypocritical and cruel servant in Que te perdone Dios (a remake of 2000 telenovela Abrázame muy fuerte).

[18] According to Juan Osorio, Moussier's illness traveled from her spinal cord to her brain, affecting her ability to remember her lines and causing her such pain that doctors were forced to put her under sedation.