"We usually use humor to make things easier to get through. But it was a pretty light mood, all things considered," said Tyler Alexander, Vice President of Brand and Marketing, The Second City.
Officials said a grease fire broke out around 12:42 p.m. Wednesday in the kitchen of Adobo Grill, which is located in the 1600-block of North Wells Street.
The restaurant occupies the first floor of the 100-year-old building. The flames spread to the second and third floors, where The Second City's administrative offices are located.
Most of the theater's historic archives and memorabilia are kept at a different location. The biggest concern was for Second City's main stage.
PHOTOS: Crews battle Old Town restaurant fire
Thick smoke billowed out of the roof as fire crews poured water into the building. It collected on the floor above the main stage. At one point, the water was two feet deep. In order to protect the stage, it had to be diverted to various sides of the building.
As firefighters worked to control the blaze, Second City kept its signature sense of humor, tweeting, "ICYMI: Yes, there's a fire. And we're working on it. #YesAnd #YesAndLifestyle"
The fire was extinguished around 3:55 p.m. Second City posted a note on its Facebook page, which said everyone got out safely and that the Chicago Fire Department handled the fire well.
Four Chicago firefighters and one other person were taken to local hospitals, where their conditions stabilized.
"I've never been through a fire. This is my first fire. I guess it went pretty well for a first fire," Alexander said.
Old Town resident Michael O'Meara and his son, Tristan, walk by the building every morning.
"I just came by here this morning and it's such a shame," O'Meara said. "Hopefully it will be fixed sooner rather than later."
City building inspectors evaluated the damage Thursday morning. They said the second and third floors were destroyed, but the main stage area was virtually untouched. Second City released a statement Thursday that said, although its "theaters were mostly spared, they will require some repair." They expect to have a more "concrete timeline" by Monday.
That means all performances for The Second City Mainstage, The Second City e.t.c., UP Comedy Club, de Maat Studio Theater and Donny's Skybox are canceled this weekend. All classes scheduled for Friday are being held at Hubbard Street Dance Studio. Officials are looking for a place to hold this weekend's classes.