Her film debut was alongside her father in Quattro bravi ragazzi (1993), and later took part in Jack Frusciante Left the Band.

Placido's other movies include Ora o mai più, by Lucio Pellegrini, Che ne sarà di noi, by Giovanni Veronesi, and Ovunque sei, directed by her father.

In season two, she plays Caterina Boldieu, a former French intelligence officer, who is assisting Frank Martin, the Transporter.

In 2006, Placido released, under the name Viola, her first album as a singer, Don't Be Shy..., including 10 tracks she wrote (most of which are in English), inspired by Stuart Benson.

Subsequently, she collaborated with the Italian singer-songwriter Bugo in the remake duet version of his song "Amore mio infinito".