The special crossover episodes featuring NBC's three "Chicago" series begins when the firefighters from "Chicago Fire" work with the medical team from "Chicago Med" to save one of their own men. The episode airs on Tuesday, Jan. 5.

Series executive producer Matt Olmstead revealed that the crossover special will start with what looks like a typical call for action to save a woman who seems to be committing suicide.

But when they take her to the medical team for proper treatment, they discover that she is undergoing a mysterious medical condition that could be linked to a previous case that previously made the headlines. This was after a doctor was suspected to be misdiagnosing and overprescribing chemotherapy treatments. This case requires the help of the police officers because the incident suddenly turned into a murder investigation.

But before they deal with the case, the "Chicago Med" team will help the members of the "Chicago Fire" department treat Herrmann (David Eigenberg) after Freddie (Ralph Rodriguez) attacked and stabbed him before the series took a winter hiatus.

Meanwhile, NBC also released the episode synopsis for "The Path of Destruction," which will air after the crossover special, on Jan. 19.

The official synopsis for the episode reads:

"A tornado threatens the city and Herrmann discovers the path may hit close to home. Chili (Dora Madison) and Brett (Kara Killmer) lock heads when Chili makes a critical mistake that leaves a victim breathless, prompting Brett to report to Chief Boden (Eamonn Walker) regarding Chili's erratic behavior. Meanwhile, Otis (Yuri Sardarov) pleads for Dawson (Monica Raymund) to help him solve his women troubles and Severide (Taylor Kinney) is asked to lend assistance to agent Alex Ward (guest star Liza Bennett) from the Department of Homeland Security regarding a suspicious home."