Megan Fox cancelled her appearance at the Midnight in the Switchgrass premiere on Monday night due to the rise of Covid-19 cases in Los Angeles.
The absence of 35-year-old Fox, who plays an FBI agent in Randall Emmett's crime thriller, was only confirmed by a representative just a couple of hours in advance.
"Due to the recent California mask mandate and rise of COVID cases, Megan Fox will no longer be attending the premiere tonight," an email to press covering the event read, reports Variety. "We appreciate your understanding."
The indoor screening at Regal LA Live was preceded by an outdoors red carpet.
Sistine Stallone wore a silk green dress and gold heels to the premiere, which was also attended by fellow cast members Emile Hirsch, Lukas Haas, Caitlin Carmichael and Olive Abercrombie.
From 11:59 pm on Saturday, LA's indoor mask mandate was reinstated, even for those people fully vaccinated, because of a sharp rise in Covid-19 cases and hospitalisations.
Last week, it was announced that reporters and photographers were banned from the premiere's after-party in a bid to limit attendance numbers.
Bruce Willis plays an FBI agent in Midnight in the Switchgrass, which is based on a true story about the most dangerous serial killer in Texas. It also stars Machine Gun Kelly, whom Fox began dating after meeting on the set.
The film, which sees Emmett taking on director duties for the first time, is released in U.S. cinemas on 23 July.