Finally! Barry Allen at long last remembered a huge spoiler about his own future that his future-self told him almost a season ago.

One of the big DeVoe spoilers revealed in Season 3 of The Flash was when Savitar (with his suit) strolled through S.T.A.R Labs with Barry and Iris. He wistfully remembered that time Team Flash made the “cerebral inhibitor” to stop DeVoe. Inexplicably, Barry and Iris totally forgot about this hugely helpful bit of information — until now.

In The Flash’s “Subject 9” episode on Tuesday, Cecille and Harry Wells bump into each other and wind up becoming friends. Harry mumbles something about wanting friends his own age, and Cecille needs help blocking out Joe’s dreams. (Remember, her pregnancy gave her telepathy.) It’s a fun, seemingly pointless B-plot until Harry realizes he can invent a device, and he also builds one that can theoretically work on DeVoe.

Except it doesn’t this time around.

Harry Wells might be the one to outsmart The Thinker ... eventually.

The Flash spent a bit of time and energy setting up DeVoe as this season’s big bad even back in Season 3. From the distant future, Abra Kadabra name-dropped DeVoe as one of Barry’s greatest enemies, and then the name came up again from Savitar.

Somehow, both Barry and Iris totally forgot about Savitar’s tip until now. To be fair, it’s been almost a year for them at this point. Barry was trapped in the Speed Force for six months. And then he wound up in jail. Okay, they’ve had a lot going on so maybe we can forgive them for this?

If only they had listened to Savitar-Barry.

Still, The Flash might’ve finally revealed how Team Flash is going to stop The Thinker. We’ve still got three more bus metas left, and DeVoe is now more powerful than ever since he acquired the powers of Izzy Bowen.

But the cerebral inhibitor, once they get it working, will hopefully prevent DeVoe from swapping into any more bodies. It will almost definitely block his telepathy, and for all we know, it could slow down his brain processing enough that Harry Wells might catch up to his level of brilliance.

We can’t possible know what’s in store for Team Flash, but we’ll definitely see them do more with the cerebral inhibitor in the future.

The Flash airs on The CW on Tuesdays at 8 p.m. Eastern.