The next Chicago Fire episode will showcase a new side of Matthew Casey, one that his friends are concerned with.

The episode teaser shows Casey starting a fight in a restaurant while having dinner with his lady Gabriela Dawson, who urges him to stop.

"That was not you last night," Dawson tells Casey. "I've never seen you act that way in my life."

In another scene, Casey also tells fireman Kelly Severide that his accident has caused some memory loss.

"I don't remember the two days leading up to the accident," Casey says.

A concerned Severide then asks Casey if he's told Dawson about his condition.

In a previous episode of season 2 titled "Not Like This," Casey was shown saving the life of a crying baby, who would have been killed by a house fire. As the firefighter tried to escape the building, a beam collapsed on him. He was later seen in surgery.

According to the forthcoming episode's synopsis, Casey will attempt to make everyone, including himself, believe that he's recovered since the accident. However, all evidence reveals he hasn't.

The episode titled "Out with a Bang" will air on Tuesday, Jan. 14 at 10/9c on NBC.