The firefighters of "Chicago Fire" come to the aid of more than a dozen people who find themselves trapped after a building collapses in an all-new episode titled "Where the Collapse Started."

In the penultimate episode of the season, the team will have to work quickly to rescue all the people still stuck inside the building. With the structure already close to collapsing, Chief Boden will have to make a difficult decision that will have deadly repercussions.

Based on the promo for "Where the Collapse Started," Boden orders all the firefighters to evacuate with less than a minute to go. The fire causes the building to explode, and viewers are left wondering whether everyone was able to evacuate safely. Unfortunately, the promo hints that one may not make it out alive.

The upcoming episode will also continue to follow Dawson's quest in fostering baby Louie. In last week's episode, Dawson found herself going through the process alone after Casey told her that he was too busy with his political responsibilities. Thankfully, a familiar face will show up to help her and give her a better chance with getting approved.

Meanwhile, the recent developments will put Casey and Antonio at odds. According to executive producer Matt Olmstead, after learning of his sister's decision, Antonio confronts Casey and asks him about his plans. If Casey and Dawson are together, then he should support her decision to foster Louie. If not, then he should let Dawson go and let her live her own life.

Despite the dramatic storylines of the episode, viewers will still be treated to some lighthearted scenes. In a sneak peek for the upcoming episode, Otis drops by the firehouse while on medical leave. He is introduced to Ferguson, a floater that Connie assigned as Otis' temporary replacement. Ferguson appears to be well liked by the entire firehouse, which leads Otis to feel uneasy about possibly being replaced.

Also in the episode, Severide's relationship with Kidd continues to bloom outside the firehouse.

Be sure to catch "Where the Collapse Started" airing on May 10.

"Chicago Fire" airs every Tuesday at 10 p.m. ET on NBC.