The Mummy: Tomb of the Dragon Emperor stars Brendan Fraser as explorer Rick O'Connell, along with his son Alex (Luke Ford), wife Evelyn (Maria Bello, taking over the character from Rachel Weisz) and her brother, Jonathan (John Hannah). The two parents are now retired, but they must stop the resurrected tyrannical Han, the Dragon Emperor (Jet Li), a mummy awoken from a 2,000-year-old curse, and whose army was found by 18-year old Alex. The Emperor now wishes to rebuild his empire, and threatens to plunge the world into his merciless, unending service with his Terracotta Army. Their chances of stopping him are thin, for the Emperor has not only an army of great magnitude, but controls the five elements. The undead Terracotta Army faces another, smaller, raised-from-the-dead army made of the Dragon Emperor's enemies, who died when they were crushed under the Great Wall of China.

In November 2001, director Stephen Sommers, who directed the previous Mummy films, said about directing a third Mummy film, "There's a demand for it, but most of the gang would only be up for it again if we could find a way to make it bigger and better." In May 2004, Sommers expressed his doubts about having the energy to make a third Mummy, though the cast of previous films had expressed interest in returning. In December 2005, a review of a script written by Alfred Gough and Miles Millar was about a Chinese mummy (China's first emperor, who wants to take over the world with his army of accursed warriors in 1940. The idea of the Han Emperor and his army is based on the real-life Qin emperor Qin Shi Huang, who was buried amidst thousands of crafted and fired terra cotta soldiers, called the Terracotta Army, believed to date back to 210 BC.

In March 2006, actor Oded Fehr said Sommers had told him a third film was in development and being written, with only Brendan Fraser and Rachel Weisz's characters returning for the sequel. The following September, director Joe Johnston was offered the helm by Universal Pictures, who hoped to start filming early in 2007. Later in the month, Weisz expressed interest in reprising her role.

In January 2007, Universal announced that Stephen Sommers, director of the first two Mummy films would not be attached to direct the third film. It was then announced that Universal entered talks with director Rob Cohen to take the helm from Sommers as the director of the third Mummy. Later in the month, the story was revealed to center around Brendan Fraser's and Rachel Weisz's characters, as well as their now grown-up son. Negotiations with the actors were in progress at that time. In February, casting began for the role of Alex O'Connell. In addition, the character of Jonathan, and previously portrayed by John Hannah, will return for the sequel. Also in February, director Rob Cohen mentioned that Jet Li and Michelle Yeoh will star in the movie although the official confirmation was not published until May.

In April, Fraser re-joined the cast for The Mummy 3, though Weisz did not due to the script issues. The film was shot in Montreal and China. The movie was reported to be titled The Mummy 3: Tomb of the Dragon Emperor. In April, Luke Ford was cast as Alex O'Connell,[18] and in May, Maria Bello was cast to replace Weisz in the role of Evelyn. Bello reported during an interview that the new "Evy" is different from the original "Evy". "She has the same name, but she's quite a different character," said Bello. At a News Conference in Shanghai, Bello told the audience 'Rob (Rob Cohen) created a new Evy ... in the first two Mummy's she was all actiony and lovely, but this Evy might be a little more ... forceful in terms of her martial art skills and shooting skills'.