8 details you may have missed on the mid-season finale of 'The Walking Dead'

• Warning: There are spoilers ahead for "The Walking Dead," season nine, episode five, "Evolution."
• On Sunday's mid-season finale of the AMC show, we learned a bit more about the strained relationship between the communities, were introduced to the series' next big villains, and said goodbye to a fan-favorite.
• There aren't too many direct callbacks to moments from the comics and show on this week's episode. So INSIDER caught up with showrunner Angela Kang and she told us some fun tidbits about Sunday's episode.
• Keep reading to see what you may have overlooked on the season nine mid-season finale. 

Negan has a baseball toy sitting in his window sill.

It's an obvious nod to his beloved barbed-wired bat, Lucille, which was taken away from Negan after the Savior war was over.

He's seen in the cell tossing a ball with a baseball glove. It's a nice touch if you're familiar with the comics and know that Negan was a gym teacher and coach before the zombie apocalypse. 

The pig reminds us of when Negan visits Alexandria on season seven, episode four and knocks on the gate saying, "Little pig, little pig. Let me in!"

Everyone disappears when Michonne and the others show up at the Hilltop. Her group is treated differently.

Everyone looks at Michonne sort of teary-eyed. Their weapons are confiscated until they leave the Hilltop.

"It's something that obviously Michonne and Daryl, they both experienced something. There's probably others that are affected in various ways, if not in the same ways," showrunner Angela Kang told INSIDER. "It's one of these character, intrigue mysteries that we wanted to sort of show to the audience a little at a time."

"We start with the effects of everything that's happened in the past and then we'll learn what exactly did happen and how it is that they came to kind of take on the positions that they did and things they've been through together," she added.

You can read more on what Kang told us about the mystery "X" marks here.

Earl Sutton asks Henry if he wants to join him and Tammy for dinner.

The two lost their child, Kenneth, on the season premiere. Henry probably reminds Earl of his lost child.

Daryl used an alarm clock to try and change the direction of a group of walkers. It's something we've seen Enid do before.

On season five, episode 15, Enid used a kitchen timer to distract a walker while she and Carl were running around in the woods. 

Did Enid inspire Daryl to start carrying around some extra alarms?

Henry's drinking scene with the kids at the Hilltop felt a lot like a scene from "Fear the Walking Dead."

Henry meets three new kids at the Hilltop and agrees to sneak out of the community late at night with them to drink. The trio bring him to a walker they keep hidden and torture. Henry gets upset and kills the walker quickly.

The scene feels a lot like one from the series' spinoff, "Fear the Walking Dead." On season three, Alicia hangs out with some teens soon after she enters a ranch with her mom. The group start drinking some homemade alcohol and doing drugs before she gets introduced to a disembodied zombie head. 

The biggest difference is that Alicia was a bit more receptive to the kids' antics. 

The three kids Henry meets are reminiscent of some bullies Carl eventually meets at the Hilltop when he goes there to apprentice with the blacksmith.

Negan's escape from his cell is straight out of the comics. It just happens a little differently.

Negan's cell is also left unlocked in the comics, but it isn't by Gabriel. Olivia, still alive in the comics at this point, leaves Negan's cell unlocked after she fumbles with the lock.

Negan considers leaving but ultimately decides not to in order to gain Rick's trust. (It doesn't really work.)

Later in the comics, after the Whisperers are introduced, Negan is let out of his cell by an angry teen, who is actually Tammy's son in the comics. Negan heads off to go infiltrate and take down the Whisperers from the inside.

"We've obviously deviated a bit from the comics at this part of the story," said Kang, noting that we won't have to wait long to see what he gets into. "When we open up in the first episode back in the new season, we will find out what it is that Negan is up to."

A scene teased for the season premiere on "Talking Dead" showed Negan up to no good with a shovel. 

If you noticed a pulsating heartbeat sound in the background toward the end of the episode, that was the idea of composer Bear McCreary.

Kang told us the goal of the episode was to bring some scares back to "The Walking Dead" and to root the show in horror a bit more.

"That episode in particular really we kind of dove in to full horror genre, just playing the suspense and the creeping horror of it all," said Kang. It's written by David Leslie Johnson-McGoldrick, whose incredibly accomplished features horror writer as well as for the show and then I have to give a ton of credit to our composer Bear McCreary, whose an incredible composer."

"He came in with this idea for what that scoring was after we kind of talked about what we wanted the feel of the sequence to be and I just loved it," Kang continued. "I just thought it felt so right because I did feel like it had that real thumping, pulse pounding rhythm. It felt like the music was inside your head and inside your chest and so a ton of credit goes there, and obviously our director, Michael E. Satrazemis did an incredible job making all the elements come together." 

Bonus: The Whisperers were first hinted at a long time ago on the show back on season three.

If you're a longtime viewer, you may remember that Morgan had said something about seeing "people wearing dead people's faces" to Rick back on season three of the show. You can read more about that scene here.

At the time, it sounded like ramblings of a delusional man, but now it makes a lot of sense. Daryl showed Michonne near the episode's end that the walker who attacked Jesus was nothing more than a man wearing a dead person's face. 

Did Morgan come across the Whisperers at some point or was this just a fun Easter egg to comic fans?

Follow INSIDER on Facebook.

ncG1vNJzZmivp6x7o8HSoqWeq6Oeu7S1w56pZ5ufony4rcukoKefXZmyorCMrJyaq5%2Bjenp5xKmgrKeUmnp5ecGrnJqjlKTEr3mRaWhxZWFm