TV Article Mary Poppins Returns: Colin Firth in talks to join cast By Marc Snetiker Marc Snetiker Marc Snetiker is a former senior editor at Entertainment Weekly. He left EW in 2020. EW's editorial guidelines Published on October 19, 2016 09:58PM EDT Photo: Jimi Celeste/Patrick McMullan via Getty Images Another sophisticated Brit is joining the world of magical nannies. EW has learned Colin Firth is in talks to join the cast of Disney’s upcoming Mary Poppins Returns, which stars Emily Blunt as the titular caretaker and Lin-Manuel Miranda as a whimsical street lamplighter named Jack. Firth will play William Weatherall Wilkins, the balloon-obsessed gentleman manager of Fidelity Fiduciary Bank, which once employed Mr. Banks. Variety first reported the news. David Magee (Life of Pi) has written the script. Rob Marshall (Into the Woods) will direct as well as produce alongside Marc Platt and John DeLuca. Mary Poppins Returns arrives in theaters on Christmas Day in 2018.