No, Jennifer Lawrence isn't going to be in the Hunger Games prequel
Jennifer Lawrence denies a rumor that she's going to appear in The Hunger Games: The Ballad Of Songbirds And Snakes

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Jennifer Lawrence Photo: Jamie McCarthy
Lionsgate is trying to recapture some of that old magic by reviving The Hunger Games, adapting Suzanne Collins’ prequel series The Ballad Of Songbirds And Snakes. It’s got lots of the ingredients you loved from the first time around, namely a plucky poor girl from District 12 (Rachel Zegler) who has to navigate the cruel excess of the Capitol as well as a fight to the death with a bunch of other kids. One thing it won’t have, though, is Jennifer Lawrence, says Jennifer Lawrence.
During Lawrence’s appearance on Watch What Happens Live, host Andy Cohen shared a fan question: “Is there any truth to the rumor you will appear in The Hunger Games prequel as Katniss’s grandmother? It does take place like, 49 years before The Hunger Games.”