Nolan took over five years to write the screenplay after deliberating about Tenet 's central ideas for more than a decade. Pre-production began in late 2018, casting took place in March 2019, and principal photography lasted six months, from May to November, in Denmark, Estonia, India, Italy, Norway, the United Kingdom, and the United States. Cinematographer Hoyte van Hoytema shot on 65 mm film and IMAX. After delays due to the COVID-19 pandemic, Tenet was released in the United Kingdom on August 26, 2020, and in the United States on September 3, 2020, in IMAX, 35 mm, and 70 mm.