The re-shoots needed to replace Kevin Spacey with Christopher Plummer took eight days to film at a cost of $10 million. It also involved Mark Wahlberg and Michelle Williams having to return to the Rome set during the Thanksgiving holiday of 2017.
After Kevin Spacey was replaced by Christopher Plummer, director Ridley Scott decided not to show Plummer any footage of Spacey in character, or even tell him how Spacey played the scenes. When finished, Scott found both performances to be quite different and equally effective in their own particular styles.
Jean Paul Getty was eighty years old when his grandson was kidnapped. Kevin Spacey, at age 58, had to be prosthetically aged to resemble Getty, whereas his replacement Christopher Plummer, at age 88, needed no special makeup applications.