And the Quantico terrorist is...Liam O'Connor!

If last week's episode didn't convince you of Drew's (Lenny Platt) role as the Grand Central mastermind, give yourself pat on the back. The real culprit was never a NAT, it was their meddlesome mentor.

If you're wondering if this is another fake out or a puppet on a string, you can put down your conspiracy playbook. According to series creator Josh Safran, Liam (Josh Hopkins) is the real deal.

"We talked about it a lot, but the reality is when you hear the why, it's more about how this is a cautionary tale of who you could be," Safran told Entertainment Weekly when the dust settled in the wake of "Closure." "All the secrets we carry with us, if we don't deal with them, that's who you could turn into."

You won't have to wait long to find out exactly how Liam laid out his sinister machinations, or why. In fact, if you look back at his inaugural speech to the NATS, you will start to see the picture quite clearly.

"The first five minutes of the finale are the how, and the rest of the finale is the why," Safran teased.

Just because Alex (Priyanka Chopra) and Co. are finally connecting the pieces, that doesn't mean death isn't still in the cards. Miranda (Aunjanue Ellis) is in serious trouble, and she might not be the only body on the floor by time "Yes" comes to a close.

"The bloodshed is not over," Safran warned.

Check out the summary for the season finale:

"It's graduation day for the NATS of Quantico, while, in the future, Alex and her team find themselves head-to-head with the terrorist, on the season finale of Quantico," ABC teased.

Find out more when Quantico airs Sundays at 10 p.m. ET on ABC. Click the video below to see a preview for the series' next episode, "Yes."

Tags: Quantico television ABC