Herrmann is home, checking out his hearing aids in the mirror. Cindy assures him nobody will even see them, let alone think of him. He feels old.

Boden and Stella welcome Derrick Gibson to Firehouse 51, sparking concern in others.

Cruz's been confirmed for the lieutenant's test at the end of the month. Boden says he's earned the right to chart his own course. Cruz looks unsure.

Herrmann arrives at the guys pulling his leg about his hearing, and the first thing he does is thank Ritter for nagging him. He probably saved his life.

Violet is teasing Sylvie about her bachelorette party when a girl asks for help by mouthing the words. She's in trouble, and Violet and Sylvie take off after the car.

They run through a red light in their pursuit of them but without light or sirens to avoid detection.

Severide receives an overnight package of documents. Ritter had no idea people still did that.

The guys try toying with Gibson, but he doesn't fall for it. He hears Violet and Sylvie calling about their pursuit. Boden calls the police for backup. At a light, they've been spotted. As they talk through it, the whole firehouse listens in. The guy pulls away and escapes. It's over.

Violet, Sylvie, and Boden chat with Detective McDaniel about what they saw. The girls don't have faith, and Boden allows them to do some more investigation, but they are still on duty.

Stella wonders how things went between Cruz and Severide. Cruz felt as if Kelly showed him the door, but Stella thinks it was done out of respect for Cruz so he could make his own choice.

She finds Kelly looking over the paperwork, and it must be arson-related because she's angry.

Carver asks Violet what happened, but Mouch interrupts with news about Gibson. A bar of soap went missing when Gibson was at Firehouse 32. The guy needs drama, that's for sure.

Van Meter stops by, and Severide wants to know if he put his name back on the list. Kelly isn't impressed and doesn't want to be pressured, but Van Meter is so impressed with his passion and talent that he doesn't want it to go to waste.

Boden reminds Herrmann that he doesn't have hearing aids because he's old but because he threw himself on a bomb.

Herrmann wonders if Gibson is 51 material. Boden doesn't think it's that simple. They need to see what they bring to the firehouse and what the firehouse brings out of them.

When Violet and Sylvie get to the donut shop, they discover that the detective was there already. They, too, want to see the footage. They see they got rid of menus, and Violet wonders if something is on it. There's a message. Call 9-1-1. I think he's going to kill me.

McDaniel accepts the menu, but he's not overly eager to help. Something seems off.

Stella is biding her time waiting to talk with Kelly. She wants to know why he would look at the file. This is something he wants to do, but she's still not understanding.

Carver has some Sherlock Holmes-level deduction skills, which he uses to determine what the bad man does for a living.

They get the call about the trapped woman, and it's a nightmarish scene thanks to the weight of bottled water.

They work hard to get her free, and she might make it. Kelly and Cruz work well together.

Gibson proves useful during the rescue, impressing Mouch. Mouch also hears that Gibson was involved in something he doesn't want to talk about -- the Cicero semifinals.

Stella decides to work with Severide and his love for arson investigation, but he wants him to ask Cruz before he goes anywhere.

Vi and Sylvie find the man's car, and they get into a bit of trouble. They think the guy is insane for smashing into the vehicle, but really?

McDaniel and others arrive to arrest the guy, and the girl is rescued.

Severide asks Cruz to take care of Squad 3 until he gets back. There's no one else he trusts.

Cicero semifinals are a boxing tournament, and Gibson was a Golden Gloves contender. Why would Gibson hide that?

Ambo pulls in with damage. The paramedic chief is on her way here, wondering how they crashed the rig outside of their district.

Cruz reconsiders the lieutenant's test. It's not the right time.

Herrmann realizes the benefit of hearing aids.

The gang welcomes Gibson to the team at Molly's.

When Sylvie leaves Molly's to be a mom, Carver offers to buy her a drink. She walks away, and he wants to know why he's being iced out. She kisses him. They're going home together.

Severide and Kidd are kissing goodbye outside of their lift. Severide leaves for the investigation.