The Walking Dead creator Robert Kirkman has confirmed that Hawkins will return to the series at some point. In season 7, the character (played by Corey Hawkins) mysteriously disappeared and was never found. He had to be written out of the show at the time because Hawkins had been cast as the lead in FOX's 24: Legacy - a show that has since been cancelled.
Based on the character from the comic books, Heath first appeared in The Walking Dead season 6 premiere, "First Time Again". He was introduced as a supply runner for the community of Alexandria and helped Rick's group divert a giant horde of walkers. Like other Alexandrians, Heath had less experience in navigating through the apocalypse, but soon became a key ally in helping Rick and others deal with several threats. However, the character appeared in only one episode of season 7 and has not been seen since due to Hawkins' scheduling conflicts with the aforementioned 24 spinoff TV series.
At New York Comic Con 2017, Kirkman answered a question about the possibility of Heath returning to the show:
Corey Hawkins...there is an intention to bring him back eventually. He had an opportunity to go do that 24 show, we wanted to be facilitating and allow him to do that... hopefully there is every intention that we get Heath back. It's in contract land, so... Corey is amazing. Kong: Skull Island, that 24: Legacy show he was on was super cool!
These comments from Kirkman echo previous comments made by The Walking Dead showrunner Scott Gimple. However, Gimple also mentioned that while Heath will return to The Walking Dead one day, that might not (in fact, probably will not) happen during season 8 of the show.
Heath's absence from most of season 7 was explained by the fact that he and Tara were out on a supply run across several episodes. The two were separated after a battle with walkers on a bridge. When Tara went looking for him, all she was able to find was his glasses, leaving his fate ambiguous. Now that 24: Legacy is over, the door is open for Heath to return. Since season 7 took place during just a matter of weeks, Heath's absence shouldn't be too difficult to explain.
The Walking Dead season 8 premieres Sunday, October 22nd on AMC.
Source: Robert Kirkman [via Comic Book]