Derek gets in on the idea of making a map of the human brain. It has lots of connections with a specific pattern that determines everything about us. He's been doing tests on an enthusiastic quadriplegic named Mickey. The project was actually initiated by Callie, who doesn't believe she has time to continue with it. In reality, it's because she first started the project for Arizona. In other news, Meredith is desperately trying to come up with a subject for a research grant. She doesn't necessarily want to pursue an interesting portal vein study because it's something her mother started. She eventually realizes that's no reason to not do something great.
Derek accidentally brings a coffee mug from home to work. Shane is asked to put it with the rest of his belongings. He gets a first class case of the guilts when he sees Heather's second-year lab coat in the locker next to his. To make matters worse, Jo accidently swipes the coffee mug Shane was supposed to care for. She ends up smashing it. Shane tries his best to glue it back together. Speaking of glue, Derek mentions that the adhesive product is sometimes used to cut off tumors to the brain. But trying this on Mickey, who has a mass, is too risky.
Mickey wants Derek to take out his tumor so they can continue doing tests on his brain. He's adamant about doing this no matter what the risk. Callie learns why. Mickey caused a car accident that killed two teenage girls. He wants to make up for that. Derek operates on Mickey, but things go south. The patient dies on the table. It's sad, but it was Mickey's call. He may be gone, but they can still study his brain to help others. Callie lets Derek know that she's back on board with their project.
A patient, Ben, has a lot more than the ankle fracture he came in for. The guy has a huge tumor in his heart. This isn't news to Ben and his wife. They've embraced the fatalness of the situation by spending gobs of money to live life to the fullest in the time Ben has left. Shane asks Cristina if the glue they sometimes use for brains can also heal the heart. If it works, it could save Ben's life. That's horrible news for the patient and his wife who were planning to pay their creditors with life insurance money. On the bright side, there's a chance he could die on the table. Sadly, Cristina is too good. Ben lives. This devastates the debt-ridden man and his wife.
Jo fears Alex may be seeing someone else because he's been staying out late the past few nights. She also has trouble diagnosing why Richard's shoulder is hurting. Tons of tests are done before Jo finally orders an ultrasound. She ultimately diagnoses the problem. This has Richard finally feeling like he's in good hands. As for Alex, he's been spending his nights at a bar watching his dad's band play. He never lets on who he is even though the two of them end up chatting and playing guitar together on stage.
Leah is in love. Well, she thinks she's in love with Arizona after having such an "amazing time" with her the other night. They had a little make-out session which Arizona now regrets. Alex says that when Leah falls for someone, she falls hard. Arizona is advised by visiting surgeon, Emma (the doc Owen is dating), to be honest. So she lowers the boom on the love-struck intern. Leah is hurt. She never really opens up to people and she thought there was a connection. Arizona may feel the same way, as she texts Leah later that night to say hey.
In random relationship news, Stephanie realizes that the kiss she shared with Shane didn't really mean all that much to him. Just as Alex starts to soften about his dad, he discovers that the guy left another family behind. He tells the guy that this other kid is better off without him before punching him in the face. Alex later yells at Jo for pushing things with his deadbeat dad. He never knew he could, once again, feel as crappy as he does now.
When Emma learns that Cristina is Owen's ex, she realizes he may not be ready to date just yet. She gives him a goodbye kiss which looks like something else to Cristina, who tries to have a chat with her person. Unfortunately, Meredith is busy with her research project. She's also still ticked at Cristina for pushing her aside when she needed her. Meredith will need time to pursue this portal vein project. Derek is willing to give it to her by scaling down his surgeries, spending time with kids and focusing on his research. He then puts away the cracked mug from earlier. All the pieces fit together proving that some puzzles can, indeed, be solved.