The BAU will have to face their next case without the expertise of FBI Special Agent Derek Morgan, after actor Shemar Moore announced that he will depart from the show after episode 18. But executive producer Erica Messer said that no one will take his place in the upcoming episodes of "Criminal Minds" season 11.

In an interview with TVLine, Messer revealed that they made a decision not to introduce a new BAU agent in the next four episodes of the current season because they want the team to "actually move on" from Morgan's departure.

She explained that fans may not appreciate the introduction of a new character after the heartbreaking decision of Morgan to quit his job for the sake of his loved ones.

"It didn't feel like the fans would fall in love with anybody new who came in under those circumstances," Messer said.

The executive producer also revealed that aside from Penelope Garcia (Kirsten Vangsness), Spencer Reid (Matthew Gray Gubler) will also have the most difficulty in moving on after one of his closest colleagues bids farewell to the team.

"Losses effect Reid in a different way than everybody else, because those connections are so strong with him," the executive producer stated.

Reid was deeply affected when Special Agent Jason Gideon (Mandy Patinkin) quit the team and was eventually murdered, which explains why it will be hard for him to accept another loss in his life.

"Reid is probably rationalizing in his brain that Derek's not gone forever in the way that Gideon is, but, 'He's still a person in my day-to-day life that won't be here anymore.' When he said, 'I don't know what this room looks like without you,' there's something really real about that," Messer added.

While CBS has yet to announce the plot for episode 19, "Criminal Minds" writer-producer Karen Maser posted a behind-the-scenes photo of a bus depot façade where the upcoming episode was filmed. She also revealed that the episode will be called "Tribute," and it was written by Virgil Williams.

The episode is slated to air on Wednesday, March 30.