If there was ever any doubt about Castiel's ( Misha Collins) ability to slay whatshername and her Lucifer-nephilim-monster-baby when Supernatural stops screwing around and gets back to its main story this season, "Lily Sunder Has Some Regrets" reminded us all that, pre-Winchesters, Castiel was kind of a tool.

He never dreamed of questioning a superior's orders, even when those orders flew in the face of what we now know is a Big Deal among the heavenly host — knockin' up an icky human — that makes every angel feel a little woozy for a sec while the opening credits of Look Who's Talking play out in some clueless chick's baby oven.

Castiel knew when Lucifer made a little monster baby with his assistant. He felt it. But apparently, over a century ago, he wasn't able to feel it when Professor Lily Sunder (Alicia Witt) got it on with her angelic research partner and, it turns out, did not make a magical hybrid baby after all. Cas totally helped his then-unit slay what turned out to be a regular old human girl because his boss said so, thus launching this immortal quest for revenge that eventually got them all killed. Except for Cas, because he's a nice angel now and he said he was sorry.

I get it. Everyone loves a "look at how human Castiel is now" story. Even Dean (Jensen Ackles) needed the reminder after giving Cas the cold shoulder, since last week's throwdown with Billie-the-Ambitious-Reaper (Lisa Berry) that ended with yet another dead reaper and yet another broken Winchester deal with "cosmic repercussions."

Stop feeding the Destiel monster, Supernatural. Stop it.

Misha Collins will guest star on Timeless.

There's no going back for Castiel. His years with Sam (Jared Padalecki) and Dean, through all manner of apocalyptic mayhem and heavenly turmoil, have changed him. Even Naomi (Amanda Tapping) couldn't successfully reprogram him because of his epic Dean and Sam love. We also know that Castiel used to be a total a-hole based on pretty much all of season 4, most of 5, and his own horror stories about being a part of the plagues of Egypt and a whole mess of other biblical smackdowns. Why are we revisiting this Castiel angle again? It's not like we don't have ample material on hand that, even after 11.5 seasons, the show somehow hasn't really touched yet.

For as much as Castiel's actions last week confirm what we already knew about his estranged relationship with Heaven and the other angels, Dean's anger and Sam's hand-wringing over Castiel breaking their deal also reveals some important and awesome new facts about them.

They were prepared to accept Billie's deal. It wasn't even a great deal in the long history of their deals with the supernatural, but they were going to honor it. Maybe they hadn't agreed on exactly who was going to die, but one of them was going to, and the other one was going to suck it up and deal, because their co-dependent consequences-be-damned-as-long-as-I-have-my-brother routine has almost always backfired over the course of this series. Innocent people have suffered because of their actions.

The building blocks of creation have been damaged. On Supernatural, for every Winchester victory, there's an equal and opposite defeat and the brothers have been able to see that for quite some time, frankly. They just couldn't grow past it. Their willingness to honor the deal with Billie indicates that finally, somewhere along the way, Dean and Sam have noticed their trail of carnage, and they're willing to stop it.

Castiel going off-script is a threat to that acceptance because they can't really stop him without compromising their friendship; and they understand where he's coming from. Even beneath all of his anger, Dean understands. Dean is just incapable of responding to anything difficult or unpleasant without anger. Sam's awkward attempts to get Dean and Cas to kiss and make up are a reflection of his own struggles. He understands exactly why Castiel killed Billie because up until about two or three seasons ago, Sam would have stabbed her without thinking twice. To condemn Castiel would be to condemn himself; and Sam no longer has any interest in making other people feel as crappy as he's made himself feel for the past twelve seasons.

Supernatural continues to make a big ol' mess of things.

"Lily Sunder Has Some Regrets" wasn't a total wash of an episode, if only for the points it raises about this new dynamic in the Sam-Cas-Dean bromance. But it also wasn't particularly ground-breaking or attention-grabbing. Neither was last week's return from winter hiatus. Supernatural specializes in pulling its storylines out of a slump, but I'd prefer they get to it sooner rather than later.

Supernatural airs Thursdays at 9/8c on The CW.

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