4 secrets that Jack Damon could be hiding on Chicago Fire

Jack Damon (Michael Bradway) is trying too hard. To do what? We're still not sure. The rookie firefighter seems like he wants to make a good impression on the surface, but every time he has a moment to himself, his energy shifts and something ominous shines through.

He's obsessed with Kelly Severide (Taylor Kinney), and seems to have made an indirect enemy in Darren Ritter (Daniel Kyri). He also seems to be vaguely interested in Firehouse 51's new medic, Lyla Novak (Joceyln Hudon). We think? Again, tough guy to get a read on.

Chicago Fire is coming up on its season 12 finale, so we assume we're going to find out what he's hiding and how it impacts the rest of 51. Here are some theories as to what the big reveal could be:

Jack Damon is Kelly Severide's son

This is a theory we already explored. Severide got around when he was younger, and Damon is definitely on the younger side. The Backstage profile of the actor who plays him, Michael Bradway, suggests he can play characters between the ages of 16 and 24.

Related: Wait, could Chicago Fire's newest addition secretly be Severide's son?

While he would have to be at least in his 20s, the fact that Severide is in his 40s means its very possible that he fathered a child before the show even started and didn't realize it. This would add quite the wrinkle to the firehouse and to Severide's marriage with Stella Kidd (Miranda Rae Mayo), in particular.

Jack Damon is a mole for Chief Robinson

We've already seen this storyline play out in season 12. Jared Lennox (Wesam Keesh) was sent in to be the first medic to work under Violet Mikami (Hanako Greensmith), and he spent his entire time at 51 giving her a hard time and questioning her authority. He was eventually given the boot.

Chief Robinson was the one who sent Lennox to 51 in the first place, so we wouldn't rule out the possibility that she would try it again from the firefighting side. It would explain the ominous phone call Damon made during his first episode. The one where he mentions nobody knowing the "real" reason why he's there.

Jack Damon is Kelly Severide's brother

A similar proposition to the first one, but perhaps more likely. Benny Severide (Treat Williams), Kelly's father, had a pretty turbulent personal life, and it would not be a stretch at all to suggest that he had a child two decades ago without telling the rest of the family about it.

Related: What happened to Truck 81 on the latest episode of Chicago Fire?

Kelly has struggled to make peace with his father's death over the last few seasons, so introducing a previously unknown member of his family may serve to flesh this part of his personality out. It would also make Damon's fanboy, little brother act make a bit more sense.

Jack Damon is getting revenge for a past tragedy

Jack Damon is obviously planning something based on his phone call. It's possible that if he isn't working for Chief Robinson, he could be collaborating with others to achieve his own goal. Maybe something went wrong during a rescue mission involving 51. Maybe Damon lost a loved one due to a mistake that a 51 member made.

If so, Damon could very well be targeting specific members within 51. This is admittedly the biggest stretch, but given how little we have to go on so far, we have to consider every angle.

What do you think Damon is really up to?