Alec Makes a Heartbreaking Decision for Magnus on 'Shadowhunters'

Meredith Jacobs
Spoiler Alert Freeform/John Medland

[Warning: The below contains MAJOR spoilers for Season 3, Episode 18 of Shadowhunters, "The Beast Within."]

"Break his heart to save his life," Asmodeus (Jack Yang) tells Alec (Matthew Daddario) in Monday's episode of Shadowhunters. In doing so, Alec would be breaking the hearts of "Malec" fans everywhere.

And he does, because he sees how miserable Magnus (Harry Shum Jr.) is without his magic and mortal.

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The series' final season airs in February on Freeform.

Prior to "The Beast Within," Alec was planning to propose. However, Magnus came home, drunk and depressed over not having his magic anymore. "I'm just a has-been warlock who isn't good for anything," he said. "What I'm feeling now, it may never pass."

To help his boyfriend, Alec turns to the only person who can help: Magnus' father, Asmodeus. Refusing to risk him escaping Edom in Hell, Alec has a warlock channel his spirit through her. Asmodeus agrees to return his son's magic and immortality for a price: Alec must break up with Magnus and can't tell him why.

(Freeform)

"You are the source of all of his suffering," Asmodeus says. "You make him vulnerable, weak. With you, he'll never reach his full potential." If Alec refuses, "then I'm afraid you will be the death of him," the Prince of Hell continues.

Alec confides in both Jace (Dominic Sherwood) and Izzy (Emeraude Toubia), though he only tells the latter everything.

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As much as it pains us to say goodbye, we're lucky to be able to still watch these warlocks, werewolves, and vampires in future series and films.

"What if you could [break Clary's connection to Jonathan], but as a consequence, you could never see her again?" He asks Jace. The other Shadowhunter admits that he can't go through losing Clary (Katherine McNamara) again, no matter how selfish that is.

Izzy tries to talk Alec out of agreeing to Asmodeus' deal, but Alec argues that he's not the first, nor will he be the last, person Magnus has loved.

"Breaking up is going to hurt like hell, but it's the kind of hurt he can recover from," he tells her. But she wonders aloud if Alec actually can recover, and he doesn't answer her.

(Freeform)

Meanwhile, Magnus spends time with Alec's mother, Maryse (Nicola Correia Damude) and admits he hasn't been handling his transition to ordinary human that well. "I don't know what I'd do without your son," he says.

That makes it even more heartbreaking when Alec tells Magnus he needs a break from them, citing his claim that he'd never be happy without his magic. He was being "honest," Alec says.

(Freeform)

"I'm in pain," Magnus admits. "But your solution to break up, how is that going to fix anything?"

"There is no fixing this," Alec tells him.

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"Days ago, you told me that you couldn't bear to lose me," Magnus reminds him. Then comes the line that hurts the most. "Days ago, I didn't know the spark inside of you, the one I fell in love with, was out for good," Alec says.

With a kiss goodbye, Alec leaves.

But this can't be the end for "Malec," right?

Fans are upset after the latest development in this relationship on Shadowhunters.

However, some do understand why Alec did what he did.

How are you feeling after that emotional episode? Sound off with your thoughts in the comments below.

Shadowhunters, Mondays, 8/7c, Freeform