Joe West (played by Jesse L Martin) was absent for much of The Flash season 5, despite the character having been a central part of the show since season 1. The Flash has always had somewhat of an interchanging cast, with supporting characters like Jay Garrick and Nora Allen coming in and out from season to season, while the core six characters: Barry, Iris, Cisco, Caitlin, Joe, and Wells, have always been present — yet, Joe was missing for most of season 5.

The Flash season 5 saw a drastic reduction in the role of a main cast member: Jesse L Martin's Joe West. Joe West is Iris's father, a cop for the Central City Police Department, and Barry's mentor and father figure. He's aided Team Flash and supported Barry since the beginning, and has been woven into the fabric of the show, as well as the hearts of fans.

Related: The Flash Is Making A Mistake By Not Redeeming Wally West

But some fans may recall that in season 5, Joe West's screentime declined steeply, which may seem odd considering how major of a character he is, and how important he's been in past seasons. While the show explained it away (for the most part) with the excuse that Joe was offscreen taking care of his newborn child, his decreased role was actually due to Martin taking a leave of medical absence from filming due to a back injury.

Joe West The Flash

During the show's hiatus, Martin suffered a back injury which resulted in him having to temporarily leave the show after episode 4 of season 5. Prior to episode 4, eagle-eyed fans may have been able to notice that Martin was injured, due to the fact that the majority of Joe's scenes were spent sitting down or leaning against a wall.

In order to heal properly, Martin left production of the The Flash, which resulted in his character being absent for eleven episodes, returning in season 5, episode 15, "King Shark vs. Gorilla Grodd." When Joe returned in the show, his absence was explained by him taking a trip to Tibet with his son, Wally West, which covered the amount of time he was gone. While it's a little far fetched that Joe would decide to go on vacation during the Cicada crisisThe Flash has never shied away from embracing a little silliness, so the excuse worked for most fans.

After being gone for the majority of season 5, Joe returned to The Flash, where he's remained on the show since. However, Joe's brief departure isn't the only one that got fans talking — for several seasons now there, have been rumors that Cisco (Carlos Valdes) will be leaving the show; however, while the character may have been gone for a few episodes, it looks like he'll be sticking around for at least a while longer.

More: The Flash: Why Reverse-Flash Still Looks Like Harrison Wells