People's lives will be on the line when Meredith Grey (Ellen Pompeo) and the rest of the doctors from Grey Sloan Memorial Hospital return in "Grey's Anatomy" season 13.

Based on the trailer for the premiere episode of the upcoming season, Alex Karev (Justin Chambers) must face the repercussion of his false accusations at the end of season 12 that severely wounded surgical intern Andrew DeLuca (Giacomo Gianniotti).

The trailer showed that DeLuca is fighting dearly for his life in the hospital after Alex attacked him when he thought that he and Jo Wilson (Camilla Luddington) are having an affair behind his back. The rest of the hospital staff has no idea about what happened to DeLuca, but Alex's best friend Meredith knows that it was Alex who almost took his life because of a jealous rage.

"You think no one is gonna realize this is you?" Mer told Alex in the video. "You could go to jail."

Kelly McCreary also talked about the results of Alex's bad reaction in an interview with TVGuide. According to the actress who portrays the role of Alex's former girlfriend Maggie, the colleagues in Grey Sloan will have an "intense fallout" because of the event.

"The doctors in the hospital [have] to reckon with the notion that one of their own could have been so violent," McCreary said. "It causes some friction among the doctors. There's definitely sides being taken."

The photos for the premiere episode of "Grey's Anatomy" season 13 titled "Undo" had been released by Entertainment Weekly. It showed that April Kepner (Sarah Drew) and Jackson Avery (Jesse Williams) welcomed their new child.

But according to the synopsis for the upcoming episode, April and her former mother-in-law Catherine (Debbie Allen) will clash about raising the child.

The synopsis for the episode reads:

"When one of Grey Sloan's own lands in the hospital, Bailey tries to figure out what happened while the rest of the doctors jump in to help. Meredith juggles huge secrets that affect her relationships with Alex and Maggie. While Richard helps Jo with a big decision, April and Catherine clash over the new baby."

The premiere episode of "Grey's Anatomy" season 13 airs on ABC on Thursday, Sept. 22.