Rouvas was born on 5 January 1972 in the village of Mandoukion, near Corfu City on the island of Corfu, the eldest of four sons of Konstantinos "Kostas" Rouvas (an ambulance driver) and the teenaged Anna-Maria Panaretou (a duty-free shop clerk at the local airport). He has three brothers: Billy (b. Vasilios), Tolis (b. Apostolos, 1975) and Nikos (b. Nikolaos, 1991). The family was poor, and Rouvas began taking care of his brothers at age five. At age four, he exhibited athletic ability and took ballet classes as a child.

After his 2005 move to Los Angeles Rouvas studied acting and received some training from his friend, Tom Hanks. He was interested in film since childhood, and a year and a half later he received an offer from Village Roadshow. In Rouvas' first feature film, Alter Ego (of which he was also associate producer), he played a role similar to himself. Before that, he dubbed English-language animated films in Greek. When comparisons between Rouvas and the character Stefanos in Alter Ego arose (with speculation that the character was autobiographical), he replied that despite similarities Stefanos was a "much more aggressive person." Rouvas adopted a new look for the film, credited by Nitro as reflecting the emo movement emerging among Greek youth. While Rouvas was attracted some critical praise for his foray into acting, others felt that it was too early to evaluate his acting talent. Rouvas' second film (the indie Duress) was a Hollywood psychological thriller in which he played a serial killer, against type for Greek audiences, and said the film was the most difficult thing he had done in his career until that point. Giannis Zoumboulakis of To Vima found Rouvas convincing in the film's cat-and-mouse plot: "You accept the proposal from the first moments, forgetting completely that the 'bad' guy in the story is the host of X-Factor", concluding that "Going against his own image, Rouvas creates a very exceptional psycho killer. With his gray-beige, old wool coat and grimy, parted hair and without his bright smile he creates from scratch a hero that is all his." Panagiotis Timogiannakis contended that Rouvas began showing a different side of himself in Alter Ego, noting that the lighting in both films did not flatter him. Timogiannakis wondered if Rouvas had deglamourized himself to receive serious roles: "He needs to clear up whether he wants to have a career of a star or of a role player. A born role player he does not seem to be. A born star he is." The 2006 Eurovision Song Contest was a springboard for glib host roles, such as for The X Factor. Producer Giannis Latsios said that Rouvas' presence contributed significantly to the show's success, calling his first-season performance "great" and adding: "We had a program that had to do with music and Sakis, on a collective level, is an icon that the generation which participates in this show has as an idol. He is a glowing character with much higher capabilities of expression and, if he decides to continue this path, will improve. He has immediacy, critique and most of all he gave to a program a luster, which was not standard from the beginning." CANNOTANSWER

Did he act in alter ego, or just sing?

he played a role similar to himself.