Mariana's (Cierra Ramirez) infidelity will end up in a big disaster when "The Fosters" return for season 4.

In the season 3 finale, Nick (Louis Hunter) found out that his girlfriend Mariana was kissing her ex-boyfriend Mat (Jordan Rodriguez). This turned the sweet, gentle guy into an arsonist when set the theater on fire. But his vengeance does not seem to end there.

Based on the trailer for the premiere episode of "The Fosters" season 4, Nick's rage will continue. But aside for burning down a room, Nick will turn into a mad man by threatening not just Mariana and her family but the entire student body with a gun.

In the trailer, it appears that Nick is following Mariana everywhere she goes, including the shower. She also woke up while Nick was standing beside her bed with a gun. But the real danger would actually happen to Mariana's adoptive mother Stef (Teri Polo).

Meanwhile, the upcoming season will also feature the implications of the mess involving Callie (Maia Mitchell) and Brandon (David Lambert).

By the end of season 3, Callie and Brandon's mothers Stef and Lena (Sherri Saum) learned that the adoptive siblings became intimate with each other. But the problem became worse when the media learned about it. This could be a big trouble for the entire Foster family.

Will the revelation cause a rift in the family, or will they become more united after dealing with the new controversy?

The family is also expected to deal with the pain that Jude (Hayden Byerly) and Callie felt when their friend Jack (Tanner Buchanan) was killed by their former foster dad. According to early spoilers, the adoptive siblings will have different ways of showing their grief.

"The Foster" season 4 premieres on Freeform on June 20.