Nothing is scarier than a deadly disease that strikes seemingly at random, especially when doctors have no clue how to prevent or treat it.
Crossover episodes don't always work out well, but this one was powerful.
One Chicago crossovers present multiple challenges.
Viewers who don't watch all three Chicago shows may be confused by references to continuing storylines on the ones they don't watch.
And the story has to provide a realistic reason for characters from all three Chicago shows to interact.
Chicago Med did a beautiful job of that.
Past seasons might have had Haley Upton from Chicago PD's exposure to the bacteria be the only link between the three shows, and that would have been a shame.
Haley's scenes with Amanda were touching, but it was predictable that someone from Chicago Fire or Chicago PD would end up quarantined.
After all, the first responders were all trying to help outbreak victims.
Chief Boden: Dr Halstead, they tell me that flesh eating bacteria can only be spread through an open cut or wound, but my people just found five people on the same floor dead of it. How is that possible?
Danover: Could be physical contact, a handshake, or something, or people touching their nose or mouth.
Boden: Oh my God. You don't know.
Less predictable was the way everyone's terror brought both Chicago Fire and Chicago PD into the fold.
Goodwin and the Chicago Med team were already under tremendous pressure thanks to the Mayor, the media, and the fact that the body count was piling up and nobody had any answers about what was going on.
Then Chief Bowen confronted Will and the CDC specialist, demanding to know what the hell was happening and how to protect his firefighters from getting sick.
This thread was more or less dropped -- the next time we saw Bowen, he was helping deal with a riot sparked by some fake news about who was responsible for the outbreak.
But it was part of the same story about how the media's attempt to capitalize on terror helped do the bio-terrorist's job for him.
Sharon bore the brunt of the storyline.
She wanted to focus on saving lives.
But as the hospital director, she had to deal with so-called journalists that wanted to spread fear, a mayor who cared about how the situation would affect his approval rating above all else, and Voight's insistence on questioning terrified people while they were being held in quarantine.
Mayor: This city is on the verge of a meltdown and when it happens, everyone's going to be looking for someone to blame. I'm gonna make damn sure they don't point the finger at the mayor's office.
Sharon: Blame is the least of my concerns, but I am not a politician. People are dying, sir, and you are wasting my time.
Sharon is always at her best when she is butting heads with idiots who put skewed priorities over the welfare of patients, and this was no exception.
She put the new mayor in his place and refused to let the media trick her twice. I loved the way she informed them that she wasn't letting them misquote her again and walked away.
As for Voight, she may have met her match there, but he was right -- with a terrorist on the loose who had no qualms about unleashing a deadly bacteria on the city, there wasn't time to waste.
It wasn't clear how Haley could help question people when she was supposed to be quarantined herself. But she stayed in the quarantine area, so I guess that was good enough.
Besides, it was a better use of Haley than continuing to talk to Amanda.
Haley and Amanda's scenes were sweet, but it seemed like there had to be more significance to this girl than met the eye.
She was in the hospital by herself, quickly became attached to Haley, and freaked out and got sick the second Haley was released from quarantine.
It would have been a cool side story if her illness was psychiatric so that she displayed symptoms of the deadly infection after Haley left and needed a chat with Dr. Charles.
But since that didn't happen, I thought she was going to turn out she had something to do with the disease being spread in the first place.
Thankfully, that wasn't the case. By the end of the hour, she appeared to be some random teenager that Haley wanted to help.
While Infection: Part II wouldn't work well as a stand-alone episode (among other things, the attack on Mama Garcia would have been less powerful without knowing she had served everyone in Soldiers' Park), there were some Med-specific things fans could appreciate.
Haley asking Natalie about her TBI was a nice touch, and Will's conversation with Andrea, the CDC specialist, touched on his complicated relationship with Natalie without going overboard.
The break from the Philip/Natalie/Will drama was more than welcome.
Sharon: We're dealing with an infectious disease.
Maggie: If you're worried about me being immuno-compromised, don't be.
Sharon: Maggie, you're going home.
Maggie: Sharon -
Sharon: Don't fight me on this.
And Maggie's illness wasn't forgotten, as Sharon sent her home so that she wouldn't be at risk of contracting the deadly disease.
Best of all, Dr. Marcel showed his vulnerable side during the crisis.
Marcel has big shoes to fill, and the jury is still out on how well he's filling them. Sometimes he's empathetic and sometimes he's decidedly not.
He and April have already butted heads, so she was the perfect person to see his near-breakdown after he had to try to encourage a patient whose arm he had to amputate.
We need to see more of this side of Marcel to make him a rootable character, especially if he's going to be the replacement for Dr. Rhodes, which means lots of screen time.
Infection: Part II ended with a suitable cliffhanger that opened the door for Chicago PD to do its thing during the third hour.
In the meantime, what did you think of the Chicago Med installment of the latest One Chicago crossover?
Was there enough of your favorite Chicago Med characters? And did you enjoy the way characters from the other Chicago shows were used?
Share your thoughts in the comments, and don't forget you can watch Chicago Med online if you missed anything.
Chicago Med continues to air on NBC on Wednesdays at 8 PM EST/PST.
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