On Thursday's episode of Mom, Marjorie (Mimi Kennedy) is getting married - but what should be a day of celebration quickly turns tragic.

Christy (Anna Faris) and Bonnie (Allison Janney) have suffered plenty of losses, but nothing can prepare them for the news they get during Marjorie's big day, when someone close to them succumbs to drugs. The show teamed up with U.S. Surgeon General Dr. Vivek H. Murthy to film a special PSA that will air after the episode.

Catch up on all this week's Mega Buzz!

The death - yes, you read that right - will likely hit Christy the hardest, thanks to something that happens earlier in the episode. But will it lead to Christy suffering her own relapse?

Watch a preview of the episode here:

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