Tolentino auditioned in front of
Gina Alajar who turned out as her mentor in the entire run of the show. She sang "Torete" by
Moonstar88 while playing a guitar. Eventually, Tolentino and Mark Kenneth Banez was chosen as one of the official protégés for that season and one of the four protégés of Gina Alajar. Tolentino said that she joined
Protégé to hone her skills, to let the people know that she has a talent and to help her family. Mentor Gina helped her all throughout the show and Tolentino's shyness was gradually fading as the competition became tougher. The improvements in her performances during gala night was seen by the judges. Singing is considered as Tolentino's niche.
Mikoy Morales, one of
Jolina Magdangal's protégés, worked with Tolentino by composing a song entitled "Butterfly". Morales and Tolentino sang the song and
Mark Escueta, husband of Jolina Magdangal and one of the members of
Rivermaya, helped in creating the music video of "Butterfly". At the end of the competition, Tolentino was announced as the "Ultimate Female Protégé" by the host,
Dingdong Dantes. Tolentino's male counterpart in winning the competition is
Jeric Gonzales, who is also from Calamba. Weeks after winning the reality search, Tolentino, along with co-winner Jeric Gonzales, were cast in the
TGIS' sequel
Teen Gen. However, the series ended its run and Tolentino moved on to take part as the scheming "Angel" in the 2013 resurrection of the series
Anna Karenina. In mid-2013, GMA Network announced that they have chosen her to play the lead in the new daytime drama
Pyra: Ang Babaeng Apoy. In 2014, Tolentino landed the lead character of Ashley as one of the main characters in
The Half Sisters, with
Barbie Forteza and
Andre Paras. This show garnered more extensions and positive ratings, even Tolentino's acting role as Ashley also gained praises as well. She played as a villain in the drama
Once Again, led by
Aljur Abrenica and
Janine Gutierrez. She also starred in various
Maynila episodes. Finding her niche in portraying villain roles, Thea played the role of a Pheobe Ke in
Hahamakin ang Lahat that ran from the last quarter of the year till the start of 2017. Right after
Hahamakin ang Lahat, she was cast in the primetime drama
Destined to be Yours, which was the first TV drama of the Phenomenal Love Team
AlDub. She then starred in
Haplos where she plays a vengeful witch Lucille, opposite the "Healer" character Angela played by
Sanya Lopez. Tolentino also played in the movie ''
This Time I'll Be Sweeter with Barbie Forteza and Ken Chan, and also had appearances in the sitcom Inday Will Always Love You'' along with Forteza, one of the show's protagonist. One of her latest roles was a transgender antagonist named Venus Hermosa, who was played by
Jason Abalos during his role as Nathan Bravante/Catriona in the afternoon series
Asawa Ko, Karibal Ko. She has also appeared in numerous GMA television anthologies such as
Maynila,
Magpakailanman and
Dear Uge, among others, due to her impressive versatility in portraying various roles and characters. Her new project was in another villain role, where she portrayed a psycho murderer and cunning mother in
Madrasta. In 2021, Tolentino returned to the afternoon series
Las Hermanas who played Minnie Manansala, one of three protagonists, Manansala sisters. In 2022, she also appeared in the action primetime series
Lolong as the minor character Celia and played one of the four lead roles, Dahlia Morales-Chua in
Mano Po Legacy: The Flower Sisters. In 2024, Tolentino returned to the anti-heroine as Rosario 'Rose' Lirio / Terra who is the older half-sister of Amira (played by Elle Villanueva) in the afternoon drama revenge series
Makiling. In 2025, she played another antagonist role as Angela Torres, the evil stepsister of Ikit (played by
Herlene Budol) in the afternoon comedy-drama series
Binibining Marikit. ==Personal life==