The studio producing the film - 20th Century Fox - has stopped production temporarily after what is rumored to be a sudden three-day span without Singer.
Singer, you may recall, recently moved away from social media, following the resurfacing of allegations about his private life.
This is not first time that Singer has disappeared during a production.
The upcoming Queen/Freddie Mercury biopic Bohemian Rhapsody has been shut down due to director Bryan Singer's "unexpected availability" due to "a personal health matter concerning Bryan and his family".
Filming is all but done on the film, we understand, with a week or two of physical production left.
Deadline, meanwhile, has reported that Fox has been sounding out directors to potentially step in and finish the movie, should that be required. He also had brief absences during the shooting of "X-Men: Apocalypse" and "Superman Returns".
"Bohemian Rhapsody" is scheduled to hit theaters on December 25, 2018.
Mr Robot star Rami Malek will be taking on the role of Mercury while Joe Mazzello stars as Queen bassist John Deacon, Ben Hardy as drummer Roger Taylor and Gwilym Lee as Brian May. It chronicles Queen's stardom from 1975 until their Live Aid performance in 1985.