For fans of The Walking Dead protagonist Rick Grimes, the latest episode of the series was bittersweet. Star Andrew Lincoln had been written out of the long-running AMC show after lasting nine seasons, just as the network had been advertising. While most fans were expecting the character to die, however, Rick wound up flying away in a helicopter by the episode's end, with his fate left undetermined. It was certainly a surprising turn of events, but eagle-eyed viewers might have predicted what would happen if they'd noticed an Easter egg cleverly hidden at the start of the episode. As a direct reference to George A. Romero's classic zombie flick Day of the Dead, the moment provides a small hint as to what will ultimately happen with Rick Grimes.

In the beginning of Andrew Lincoln's final Walking Dead episode which aired on Nov. 4, Rick passes a mailbox labeled with the name, "Cardille." Although it seems like a random name, this is actually a reference to actress Lori Cardille, who plays Dr. Sarah Bowman in Day of the Dead. In the end of that movie, Bowman is one of very few characters to survive by fleeing from the dead in a helicopter. Referencing Cardille foreshadows the end of the episode, which has Rick surviving his series exit the same way Dr. Bowman escaped in Day of the Dead. Furthermore, a calendar in the movie reveals the date to be on Nov. 4, the same day as Rick's final episode on The Walking Dead aired.

It's not surprising to see Easter eggs for classic horror films hidden in the series. Executive producer Greg Nicotero actually worked on Day of the Dead and was close friends with the late George Romero. The iconic "Dr. Tongue" and "Bub" zombies from the film have both been featured in past episodes of The Walking Dead as well. There have also been Easter eggs for other Romero movies, such as the actual crate from Creepshow making its way into a scene. It's an interesting way for Nicotero to pay tribute to some of the show's inspirations, and they're always really fun for horror fans to spot.

Related: Rick and Shane Reunite in Walking Dead Set Photo Shared by Jon Bernthal

As for Rick's future, that fortunately will not be left as a cliffhanger, leaving what's next a mystery. A series of three made-for-TV movies from AMC will continue Rick's story, as officially announced by the network. This gives him some new adventures entirely separate from the characters and storylines the main series has built over the past eight years. It's a good way to give Lincoln the time off from the show the actor desires, while still letting the character live on to star in some new stories in the universe.

Of course, series favorites like Norman Reedus, Dania Gurira, and Melissa McBride remain behind. Although falling ratings have brought season 9 to series-low numbers, AMC has no plans to put an end to the main series anytime soon. With Lincoln now officially out, we will soon see if Rick's exit will have a heavy impact on the rest of the season's ratings. This information comes to us from ComicBook.com.