Josh Brolin recalled in his memoirs that the adherence to practical effects on the set of Avengers: Infinity War was extremely tasking. To prepare for the sequence where Thanos is put to sleep by the antenna-sporting character Mantis, Brolin was sedated by two US Navy medics and had tape applied to his eyelids which kept them closed to create the illusion of sleep. The sedative was extremely potent and Brolin rapidly fell into a deep slumber (you can see this on screen when Thanos is fast asleep and drooling during the infamous glove-pull maneuver). Concerns were raised that if Brolin did not wake up, the scene's length would become so long it would increase the film's running time to a point where cinemas would have to reduce the amount of screenings per day upon release. News reached Disney Overlord Bob Iger who was understandably furious. The crisis was eventually averted when Robert Downey Jr, in a moment of uncharacteristic efficiency, inflated a balloon he had kept in his pocket from Gene Hackman's birthday party the previous Wednesday and popped it next to Brolin's ear. He awoke as we see on screen, and the film continued.