Welcome back to Farewell to Shadowhunters, TV Guide's celebration of the final run of Freeform's supernaturally addictive fantasy series!

Clary (Katherine McNamara) seems to have finally gotten a hold on that twinning rune thanks to Jace (Dominic Sherwood), and together they managed to put Jonathan (Luke Baines) exactly where he deserves to be — in a cell in the Institute. Little did they know, Jonathan had been this close to killing his mother, Lillith (Anna Hopkins) in order to recover the Morningstar Sword from the Seelie Queen. We can't tell whether that would have been a good thing or a bad thing? On one hand, Lillith would be dead. Hurray! On the other hand... Jonathan can't have great plans for that sword, right?

We chatted about Jonathan's motives and how he still manages to inspire some conflicted feelings in us (despite all the evil and sister-kissing) with Luke Baines when he stopped by to say Farewell to Shadowhunters. While he was tight-lipped about what exactly Jonathan plans to do with Satan's sword, he did tease that we'll be seeing some effects of the twinning rune on him coming up, so maybe we'll start seeing a more angelic side of him? Don't get your hopes up too high though, Baines assured us Jonathan's still got many evil deeds on the agenda before Season 3 wraps up.

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Catch new episodes of Farewell to Shadowhunters Tuesdays at 1:00 p.m. PT!

Shadowhunters airs Mondays at 8/7c on Freeform.

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Katherine McNamara and Dominic Sherwood, <em>Shadowhunters</em>Katherine McNamara and Dominic Sherwood, Shadowhunters