Short answers, pulled from the story.
The Two Towers is the second film in Peter Jackson's Lord of the Rings trilogy, released in 2002. It follows three intercut storylines: Frodo and Sam travelling toward Mordor with the creature Gollum as their guide, Merry and Pippin escaping captivity and rousing the tree-like Ents to attack the fortress of Isengard, and Aragorn, Legolas, and Gimli joining King Théoden of Rohan to defend Helm's Deep against Saruman's army.
The Two Towers grossed $923 million worldwide during its original theatrical run, making it the highest-grossing film of 2002. Against a production budget of $94 million, it was the third-highest-grossing film of all time at the time of release. Following later reissues, its total has reached $944 million.
Gollum was created by Weta Digital using a combination of Andy Serkis's physical performance and motion capture, and computer-generated imagery. Serkis performed every scene twice, once on set with the other actors and once in a motion-capture suit. The CGI Gollum was then rotoscoped and animated on top of the on-set takes. His face was animated manually, often using recordings of Serkis as a guide, and realistic skin tones supervised by Gino Acevedo took four hours per frame to render.
At the 75th Academy Awards, The Two Towers was nominated for six awards and won two: Best Visual Effects, awarded to Jim Rygiel, Joe Letteri, Randall William Cook, and Alex Funke, and Best Sound Editing, awarded to Ethan Van der Ryn and Michael Hopkins. The film was also nominated for Best Picture.
Several significant changes were made. Faramir was given a longer arc of temptation by the One Ring before releasing Frodo and Sam, whereas in the novel he lets them go quickly. Aragorn was given a cliff-fall subplot not present in the book to increase tension. The meaning of the title was also changed: Tolkien identified the two towers as Minas Morgul and Orthanc, while Jackson's film names them as Orthanc and Barad-dûr.
The Two Towers was filmed entirely in New Zealand, concurrently with the other two films in the trilogy. Principal photography ran from the 11th of October 1999 to the 22nd of December 2000. Key locations included Dry Creek Quarry for the Helm's Deep set, Mount Sunday for the exterior of Edoras, and Stone Street Studios for interior scenes.