(UPDATED) American pop superstar Taylor Swift released her 11th studio album "The Tortured Poets Department" on Friday.

 Initially, the album, also shortened as "Tortured Poets," features 16 tracks including one bonus track "The Manuscript", but Swift dropped a surprise treat for her fans and announced 15 additional songs two hours after the original release.

The singer-songwriter called "Tortured Poets" a "secret DOUBLE album," and the second part "TTPD: The Anthology." 

"I’d written so much tortured poetry in the past 2 years and wanted to share it all with you, so here’s the second installment of TTPD: The Anthology," she said. 

Swift announced its release date on her historic night during the Grammys when she won Best Pop Vocal Album for "Midnights." 

During her acceptance speech, Swift said she "kept the album a secret for the last two years." 

Swifties back then were anticipating an announcement of "Reputation (Taylor’s Version)" at the ceremony.

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The 14-time Grammy Award-winning artist already revealed its initial tracklist in an Instagram post, including titles "My Boy Only Breaks His Favorite Toys," "Down Bad," "So Long, London," among others.

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American rapper Post Malone also collaborated with the 34-year-old billionaire for the first single of the album, "Fortnight," for which they will also release a music video afterward.

As a fan, as she called herself, Swift praised the rapper after their collab for the album's lead single.

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"I’ve been such a huge fan of Post because of the writer he is, his musical experimentation and those melodies he creates that just stick in your head forever," the singer-songwriter wrote in a social media post.

"I got to witness that magic come to life firsthand when we worked together on 'Fortnight,'" she added.

The tracklist also features "Florida!!!" with rock band Florence and the Machine.

Spotify announced earlier on Friday that 'Tortured Poets' became the most pre-saved album Countdown Page in the history of the music streaming platform.

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Check the full tracklist here.

 "The Tortured Poets Department"

 1. "Fortnight" (feat. Post Malone)

2. "The Tortured Poets Department"

3. "My Boy Only Breaks His Favorite Toys"

4. "Down Bad"

5. "So Long, London"

6. "But Daddy I Love Him"

7. "Fresh Out the Slammer"

8. "Florida!!!" (feat. Florence + The Machine)

9. "Guilty as Sin?"

10. "Who's Afraid of Little Old Me?"

11. "I Can Fix Him (No Really I Can)"

12. "LOML"

13. "I Can Do It With a Broken Heart"

14. "The Smallest Man Who Ever Lived"

15. "The Alchemy"

16. "Clara Bow"

"TTPD: The Anthology"

 17. "The Black Dog"

18. "Imgonnagetyouback"

19. "The Albatross"

20. "Chloe or Sam or Sophia or Marcus"

21. "How Did It End?"

22. "So High School"

23. "I Hate It Here"

24. "Thank You Aimee"

25. "I Look in People's Windows"

26. "The Prophecy"

27. "Cassandra"

28. "Peter"

29. "The Bolter"

30. "Robin"

31. "The Manuscript"