The Sparring Partner

The case of a double parricide becomes complicated and confusing. Two barristers represent the two defendants in court. Nine jurors with different backgrounds are involved in the debate of right and wrong in justice at the same time.

• Yeung Wai Lun as Henry Cheung, the first defendant; a Hitler admirer with an IQ of 127
• Mak Pui Tung as Angus Tong, the second defendant of the case; an accountant with an IQ of 84
• Louisa So as Barrister Carrie Yau, a senior counsel and Angus' representative lawyer
• Michael Chow as Barrister Allen Chu, a solicitor in Prosecutions Division of the Department of Justice; He can perform excellent English but is bad at Cantonese
• Jan Lamb as Barrister Wilson Ng, Henry's representative lawyer
• Gloria Yip as Wai-Ping Yip, one of the jurors; a retired teacher and housewife
• Choi Tsz-Ching as Barrister Chan Yuk-Yu, a senior counsel in Prosecutions Division of the Department of Justice and Chu's assistant
• David Siu as Cheung Shiu, DCS sergeant
• Chu Pak-Him as Hin Jo Cheung, Henry's brother
• Harriet Yeung as Man Shan Tong, Angus' sister
• Xenia Chong as Pui King Shiu, Henry and Hin's cousin; a devout christian
• Au Shiu Hee James as Kuen Kwai Cheung, Henry and Hin's father and the murder victim
• Fung-Kam Chan as Suet Yee Shiu, Henry and Hin's mother and the murder victim
• Brenda Chan Kwai-Fan as Yim-Or Suen, one of the jurors; a former principal
• Amen Au Cheuk-Man as Siu-Hung Mak, the jury foreman
• Ursula Wong Yue-Si as Mei Fan Liu, one of the jurors
• Chung Suet-Ying as Ka-Man Cheng, one of the jurors
• Yau Man-Shing as Kin-Shing Lee, one of the jurors; a merchant
• Lam Sen as Si-Kwan Ko, one of the jurors; a Philosophy graduate
• Wong Wa-Wo as Fu Ho, one of the jurors who is retired
• Kiki Cheung Hoi Kei as Ka-Yan Koo, one of the jurors; an office lady
• Nicky Wong as Little O, a DCS officer
• Matt Chow as Superintendent Kam, the DCS superintendent
• Rachel Leung as Man Yee Ho, Ng's apprentice
• Joe Cheung as judge
• Larine Tang as Mika, Angus' ex-girlfriend
• Crystal Kwok as Amanda, a magazine editor
• Myth Or Yik-Ki as Kate, a reporter who works for Amanda
• Patra Au as Little O's mother

Filming started on December 25, 2020.[6]The new director Ho Cheuk Tin has been the assistant director of the film's producer Philip Yung for many years. The Sparring Partner is based on the 2013 Tai Kok Tsui double parricide and dismemberment case. The case involves parricide, dismemberment and hidden corpses, and shocked the Hong Kong society that time.

Philip Yung revealed that he knocked on doors everywhere to find investors for The Sparring Partner, but results in nothing, and he used his savings for buying property to invest the film. Afterwards, he thanked the owner of Mei Ah Entertainment, Guoxing Lee, for agreeing to invest part of the film's expenses, as well as the film fund, and two anonymous saviors. In the end, there was still HK$1 million short. "I boldly called Mr. K. He has always loved me in the wrong way. He only said two sentences on the phone, "Listen to the number of days", "Don't thank me, and don't mention it. I, try my best to make a good movie for Hong Kong'".[7] Netizens have guessed who Mr. K is. Some hinted that it is Louis Koo, who also loves Hong Kong movies and is willing to help others realize their dreams, or Aaron Kwok, who won his first Best Actor Award with "Treading Blood and Looking for Plums", and sang "Killo Levi's Reply Letter" and "Call of Wrong Love". When interviewed by the media, Aaron Kwok responded that Mr. K is an investor in the film, but he is not an investor in the film himself, emphasizing that he supports the new director as an actor. People used different reasons to speculate whether it was Louis Koo or Aaron Kwok. Philip Yung responded by saying that he invested in the film, believing that it was Louis Koo himself,[8] and Aaron Kwok himself denied it.[9] Since the film involves parricides and subsequent dismemberment, it can definitely not pass the film censorship in China, so it can only rely on the Hong Kong local and overseas sales markets.

This is the first category III film of Mak Pui Tung, Louisa So, Jan Lamb, Choi Tsz-Ching, Chu Pak-Him, Ursula Wong Yue-Si, Chung Suet-Ying, Kiki Cheung Hoi Kei, Myth Or Yik-Ki, Rachel Leung, Nicky Wong and Patra Au. It also serves as Kicky Wong's debut film. In the meantime, this is Au Shiu Hee James' posthumous release.

Director Ho Cheuk Tin specially invited Wing Mo to act as an acting instructor at the filming scene in order to enable the actors to perform in a short period of time.

According to the movie rating system in Hong Kong, the film is listed as category III, only allowing aged 18 or above to watch.

The film had its world premiere as the opening film at the 46th Hong Kong International Film Festival on August 30, 2022. On September 1 the same year, Distributor Golden Scene announced that the film would be officially released in Hong Kong and Macau on October 27, with the first screenings began in the same month.

The box office of the film on the opening day was only HK$200,000. Although it had a good reputation, the results were not as good as expected. After a week of release, it reversed its decline and became the single-day box office champion for four consecutive days starting from November 3, 2022. As of November 6, 2022, the cumulative daily box office is HK$8,642,637, approaching the 10 million dollar mark. The box office continued to rise and created a miracle in releasing. The box office in the first week was 3,229,784, the box office in the second week was 5,404,699, the box office in the third week was 7,532,260, the box office in the fourth week was 8,503,424, the box office in the fifth week was 6,163,268, and the box office in the sixth week was 3,704,698.

Four weeks after its release (as of November 18), the box office of The Sparring Partner exceeded 20 million,[10] becoming the 11th category III film in Hong Kong to reach HK$20 million.

As of November 27, the box office has exceeded HK$30 million. It is the fifth film in 2022 to break through HK$30 million after Chilli Laugh Story, Mama's Affair, Warriors of Future and Table for Six. It is also the eighth 30 million category III film in Hong Kong. In the sixth week, the box office defeated Black Panther 2: Wakanda Forever and regained the weekly box office championship.

As of January 21, the cumulative box office has reached HK$41.6 million, becoming the 29th most-grossing Chinese film in Hong Kong, breaking the box office record of HK$41.07 million in the 2011 movie 3D Sex and Zen: Extreme Ecstasy, and becomes the champion of Hong Kong's third-level film,[11] and became the fourth Hong Kong film to break through HK$40 million box office in 2022, setting a film record in Hong Kong film history.[12]

The Walt Disney Company has purchased the exclusive copyright of the film. It was streamed exclusively online on Disney+ at 9:30 p.m. on March 25, 2023 and premiered exclusively on Fox Networks Group's Star Chinese Movies.[13]