WARNING: The following contains spoilers for The Good Doctor Season 4, Episode 18, "Forgive or Forget," which aired Monday on ABC.

The Good Doctor has been covering some heavy topics in recent weeks, and "Forgive or Forget" isn't stopping that trend. Still trying to move on from their miscarriage, Shaun and Lea decide to take a camping trip, but things soon take a turn for the worse.

"Forgive or Forget" decides to explain its title in the first scene as Claire and her father discuss their past while cleaning up dinner. Marcus wants to know if Claire's forgiven him for abandoning her as a child, but Claire isn't interested in talking, telling her father that they can either watch a movie or he can head home for the night. He decides to watch the movie, but clearly, he's not happy with her ultimatum.

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Shaun announces he's planning a camping trip for him and Lea back at the apartment. While she isn't thrilled when he first brings up the idea, she comes around after her loving boyfriend explains it's important to get out of their comfort zones as they try to move on. Around the same time, Dr. Glassman heads home, only for his alarm system to trigger when he enters the door. And when he finally shuts it off, he turns around to find his wife, Debbie, pointing a gun at him. She obviously thought he was an intruder, and after realizing he wasn't, she puts the weapon down. However, Debbie discovers Glassman unloaded the gun at some point, triggering a massive argument between them.

At the hospital, Dr. Lim, Asher and Claire tend to a young girl who has a growth on her neck. Lim has been advising her parents to allow their daughter to get surgery since she was five, but they've always resisted. However, with the growth becoming dangerous, they don't have a choice anymore. Morgan is also working on a new case, one that finds a man using mushrooms to combat depression, and after he refuses to stop taking them, she at least gets him to agree to additional tests.

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Shaun and Lea arrive at Yosemite National Park, only to be told all of the first-come, first-serve campsites have been taken. Shaun begins to argue with the park ranger, but Lea shuts it down by deciding they'll go somewhere else. Back at the hospital, Claire, Asher and Lim begin to perform surgery on the girl, and, in true The Good Doctor fashion, their conversation moves towards Clarie's personal life. Lim agrees with Marcus that they should talk about the issue, while Asher believes the past is buried. However, before the group can finish talking, the girl begins to lose blood.

Park, Jordan and Morgan run a scan on the mushroom-using patient, and, of course, Morgan and Park disagree about his alternative medicine. As they argue, Jordan points out that they never agree on anything, and they need to get closer. But before they can fire back, they discover a fungal lesion on the man's brain. Elsewhere, Shaun and Lea arrive at a new campsite, but just as Lea starts to settle in and look at a nearby lake, an RV blocks her view, running the peaceful moment.

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Lim and Claire go to tell the girl's parents about the complication and inform them that, to finish the surgery, they'll have to remove their daughter's collarbone. Obviously, this upsets them, and they want to take their child home, but once again, the choice is left in the hands of the doctors. Morgan and Park also go to discuss surgery with their patient, but he's hesitant. He wants to keep using mushrooms to fight his depression, even though they're killing him, and Morgan tries to get him to understand that he can fight without them.

Trying to figure out the best strategy, Park and Morgan head to Dr. Andrews, who tells Park he needs to make the call. Park, of course, goes with his plan, which upsets Morgan, who believes he's being biased against her. Shaun and Lea are still having a hard time acclimating to life at the campsite, and as it begins to rain, Lea decides to sleep in the car, leaving Shaun alone in the tent. Claire also makes a hard choice by deciding it's time to talk with her father, and she begins by asking why he left. Marcus explains that her mother, Breeze, told him all he was good for was money, so he left and sent checks every month. Claire tells him she never got any money, which makes Marcus speak ill of Breeze. This upsets Claire greatly, as she feels like her dad is using her dead mother as the scapegoat for his failures, and she storms off.

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Feeling bad for abandoning Shaun, Lea wakes up and tells him she still wants to go on the hike planned, despite having a rough evening. Claire, Asher and Lim once again begin operating on the girl, and they soon realize they will also need to remove a part of her lung. Knowing the parents don't trust Lim, Claire goes to ask the parents for permission alone. Glassman tries to apologize to Debbie but makes things worse when he refers to their house as "his," something he's seemingly done in the past. Back with Shaun and Lea, the couple is having a great time hiking, so much so, Lea wants to take a photo of Shaun in the wilderness to capture the moment. However, as they try to find the right angle, Shaun slips off a log and hurts his ankle.

Shaun quickly realizes his injury is severe, and he needs emergency surgery. Without any other options, he tells Lea she'll have to perform it as he guides her through it using the things at their disposal. Meanwhile, Claire tells the girl's parents about the complication but uses her conversation with her father to get them to agree. As Park, Andrews and Jordan operate on the patient, Park soon realizes that he was wrong with his approach, and they switch over to Morgan's plan. Back with Shaun and Lea, Lea begins to operate when Shaun passes out from blood loss before he can list off the steps of the procedure, leaving her with little hope.

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Glassman decides to talk to Lim about his issues with Debbie, and she tells him the reason her marriage ended was that her ex was threatened by her, which led him to become overbearing. Lea successfully repairs Shaun's ankle, and as they head to a nearby hospital in an ambulance, the EMT tells Shaun he's lucky to someone like Lea by his side. Park and Morgan's patient wakes up from his surgery, and while Morgan still believes he should stop injecting mushrooms, she tells him that growing them might be what helped him deal with his depression.

Claire witnesses the girl accept an apology from her parents, and it obviously has her feeling bad about what happened with her dad. Park confronts Morgan about their relationship, and he tells her he no longer wants to be friends. She's quick to shoot down the idea, however, telling him they can't ignore the relationship they had. Feeling guilty, Claire goes to see her father, and after she tells him he's forgiven, they embrace and agree to start things over. However, with one relationship starting anew, another one may be coming to an end. As "Forgive or Forget" comes to a close, Debbie walks out on Glassman, telling him she can't make it work anymore.

Created by David Shore, The Good Doctor stars Freddie Highmore, Antonio Thomas, Richard Schiff, Paige Spara, Fiona Gubelmann, Will Yun Lee and Christina Chang. New episodes air Mondays at 10 pm ET/PT on ABC.

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