Alexx O'Nell (born Alexander Leonard O'Neill on July 26, 1980) is an American actor and musician who is based in India and has appeared in films, series, and music videos in English and Indian languages. He is best known for Golondaaj, Roohi, Aarya, Main Aur Charles, Cheeni Kum, Madrasapattinam, Joker, Yeti Obhijaan, Chittagong and Urumi (Ek Yodha Shoorveer).

O'Nell began his acting career with community and regional theater in the United States,later working in television advertisements in India and internationally, and finally landing character roles and appearances in films such as the Hindi feature Cheeni Kum (2007) and the English feature Loins of Punjab Presents (2007). He later gained recognition as a contestant on the hugely popular Indian celebrity dance competition Nach Baliye (season 3, 2007).

O'Nell's first leading role in a big-budget production came with Madrasapattinam (2010). Following Madrasapattinam, O'Nell returned to television to star in the Indian primetime historical drama Jhansi Ki Rani in mid-2010, and in early 2011 he also appeared in a guest role on the drama Dhoondh Legi Manzil Humein. Late 2011 saw the release of the Hindi Language feature Jo Dooba So Paar (2011), with O'Nell in a supporting role. After almost a year's gap, O'Nell was seen in a lead role in Shirish Kunder's Joker (2012) followed shortly thereafter by a cameo in A. L. Vijay's Thaandavam (2012) released in late August and late September 2012 respectively. Finally, O'Nell starred in Bedabrata Pain's Chittagong (2012), released on October 12, 2012. O'Nell appeared in a double-lead role in the multilingual Urumi (2011), and the unreleased English-language Vasco Da Gama, (in which he plays a triple role) directed by acclaimed Indian director Santosh Sivan. Urumi released in select markets (Malayalam, Tamil, Telugu) in 2011 and 2012 and remains the second most expensive and second highest grossing Malayalam film of all time. The stage of completion and expected release date for the English-language Vasco Da Gama are unknown. O'Nell's next releases were the Malayalam films Gangster and Manglish, both featuring O'Nell alongside South-Indian actor Mammootty, releasing in April and July 2014, respectively. He was recently seen in the 2016 release Ek Yodha Shoorveer (2016) (a Hindi dubbed and re-edited version of Urumi (2011) ), Tigmanshu Dhulia's Raag Desh (2017), Inside Edge (2018), Bose: Dead/Alive (2018), and Doctor Rakhmabai, Sye Raa Narasimha Reddy, Trial of Satyam Kaushik and Banarasi Jasoos.