Acting was in his genes and while Prithviraj was still pursuing his degree in Australia, he was called for a screen-test by director Fazil for one of his movies. The 19-year-old Prithviraj auditioned for the role but for reasons undisclosed the project was shelved. However, Fazil then recommended him to director Ranjith, who was planning his second movie, Nandanam. Prithviraj was casted for Nandanam (2002), which technically was his debut movie. However, the movie was preceded by Rajasenan’s Nakshathrakkannulla Rajakumaran Avanundoru Rajakumari (2002), which was a box office disaster.
The actor later went on to star in movies directed by Vinayan, Lohithdas, Bhadran, and Shyamprasad. Although immensely talanted, Prithviraj’s movies did not reflect a positive outcome, with most of his movies receiving average reviews. Director Shyamprasad even stated that Prithviraj’s advantages are his talent and intelligence irrespective of his box office successes, and cast him in the lead role in his movie Akale (2004). The actor received a special Jury Mention for his role at the Asianet Film Awards 2004.
In 2005, Prithviraj made his Tamil film debut with the movie Kana Kandaen, and in the following year he appeared in the movie Parijatham (2006) opposite Saranya Bhagyaraj, daughter of actor Bhagyaraj. The movie turned out to be a hit. In the same year, he became the youngest recipient of the Kerela State Award for Best Actor for his performance in the movie Vaasthavam directed by M. Padamakumar. He was next seen in movies such as Classmates (2006), Chocolate (2007), Thalappavu (2008), and Thirakatha (2008). He appeared in pivotal roles in the movies Thalappavu (2008) and Thirakatha (2008) and was much appreciated for his performances in both of them. For his role in Thalappavu one of the reviews stated that the film, which is truly the coming-of-age film for Prithviraj the actor and that there is a spartan dignity that he brings into his commanding portrayal of Naxalite Joseph.
In 2009, Prithviraj gave a commendable performance in the movie Puthiya Mukham directed by Diphan. The media then went on to call him ‘Young Superstar’. In the same year he also appeared in the Tamil remake of his film Classmates, titled Ninaithale. In 2010, Prithviraj essayed the role of a cop in Mani Ratnam’s Tamil movie Raavanan, and also appeared as one of the main characters in Vasantabalan’s mega budget Tamil movie Kaaviya Thalaivan. In the same year he also made his Telugu debut with the movie Police Police. His role in the movie Indian Rupee (2011) was stated to be his career best performance by Nowrunning.com.
After being immensely successful in South Indian cinema, Prithviraj made his Bollywood debut in the year 2012 with the movie Aiyya opposite Rani Mukerji. The actor’s other major releases in 2012 include Molly Aunty Rocks, Hero, and Ayalum Njanum Thammil.
Prithviraj appeared in three Malayalam films and a Hindi film in 2013. The Malayalam films – Mumbai Police, Celluloid, and Memories – and his sole Hindi release, Aurangzeb – turned out to be critical and commercial hits. However, the same wasn’t the case with the beginning of the year 2014. The actor’s first release London Bridge was a box office disaster. His next two releases viz. 7th Day and Sapthamashree Thaskarah received positive reviews at the box office. In 2015, the actor starred as Varun Blake in the movie Ivide. The media termed his performances as one of his career best acts. The actor’s consistency was proven yet again in the romantic drama Ennu Ninte Moideen (2015), which is termed to be one of the greatest romance films made in Malayalam cinema. In 2016, he starred in the movie Pavada, and his other release of the year includes Darvinte Parinamam directed by jijo Anthony.