"Criminal Minds" Season 14's premiere episode will be like no other as it will be its very special 300th installment. The show will feature an UnSub that killed 300 times as a celebration to mark the show's milestone and new romances.

In an interview with the showrunner Erica Messer, she revealed "Criminal Minds" Season 14's premiere episode would feature someone "who has killed 300 people." Although this concept might surprise the fan, they might be left on the edge of their seats to know there is indeed somebody who did this.

"I looked up this Monster of the Andes who is believed to have killed in excess of 300 people and is currently missing," Messer told TVLine. So when the showrunner thinks they have already done everything in the show, they still have something new to give in "Criminal Minds" Season 14.

Messer continued to say "Criminal Minds" Season 14 would pick up the events of the previous season. However, it would be a few moments later. The rest of the BAU would be in a rush to return to Quantico to learn what really happened and try to know where is Reid (Matthew Gray Gubler) and Garcia (Kirsten Vangsness).

Meanwhile, "Criminal Minds" Season 14 would be more personal this time as it would touch the life of Rossi (Joe Mantegna), per Cinema Blend. Messer also revealed that his third wife, Krystall (Gail O'Grady), would return to the series. To recall, they got married for 36 hours by an Elvis impersonator.

Rossi's colorful love life would not end in the premiere episode as fans would see in "Criminal Minds" Season 14 Episode 2 that they still have a thing for each other. It would even continue throughout the entire season. "By the end of the season they're giving it a go again," Messer said.

Aside from Rossi, Messer also revealed Prentiss (Paget Brewster) would also meet someone in an episode of "Criminal Minds" Season 14. However, the showrunner did not reveal which episode is it or who the guy would be. But from the looks of it, fans have a lot of romances to look forward to this season.

"Criminal Minds" Season 14 is set to have 15 new episodes, but Messer teased it could go beyond that number if CBS asks for more. The show's premiere episode would mark its 300 milestones, and it would soon hit the small screens on Wednesday, October 3, at 10 p.m. E.T.