The 12^th season of "Supernatural" is expected to end with a bang, since The CW will air a two-hour season finale episode on May 18.

The network released the individual synopses of the final two hours of the season, revealing the Winchester brothers will have to face two different battles against two separate enemies.

The first hour will be called "Who We Are," which will center on the clash between the American hunters and their British Men of Letters.

In an interview with TVLine, executive producer Andrew Dabb revealed the battle will have a major effect on the relationship between Sam (Jared Padalecki) and Dean (Jensen Ackles) and the British Men of Letters.

"It's obviously a little strained. [The British Men of Letters] want everybody dead. But as they are a massive organization and very corporate in their own way, they're going about it in a very organizational, methodical way," Dabb stated.

The fighting between the two organizations will also have an effect on the Winchester brothers' mom Mary (Samantha Smith) since she was the one who brought them into the fight. "We're not creating a scenario where Mary is bending over backwards to defend the British Men of Letters [or] what they're doing. But all three of our Winchesters realize the mistake they've made, and as soon as they realize it, they start to take action to basically get the hell out of there, to varying degrees of success," the executive producer also said.

After the huge fight between the hunters and the Men of Letters subsides, the second part of the season 12 finale called "All Along the Watchtower" will focus on the Winchesters' fight against Lucifer (Mark Pellegrino). This time, they will be joined by their longtime friend and ally Castiel (Misha Collins) to help them in their battle for the control of Lucifer's unborn baby.

The CW will air the two-hour season 12 finale of "Supernatural" on Thursday, May 18, starting 8 p.m. until 10 p.m.