The NFC West, the number one seed, and a first-round bye are on the line as the San Francisco 49ers travel to Century Link Field and attempt to win in a stadium where the team has not been able to do so in the past seven seasons.
This "House of Horrors" has been a nightmare for the 49ers, where they have lost for the past eight straight games, including a 23-17 loss in the 2013 NFC Championship game.
The Niners will be like "The Losers Club" of Stephen King's "It," encountering Pennywise the Dancing Clown at the house on Niebolt Street and facing their fears to overcome the monster.
A 42-13 loss on a Week 16 Sunday night game against the Seahawks in the 2012 season was the first game that started the losing streak.
In this game, the 10-4-1 49ers had one of the league's top defenses and quarterback Colin Kaepernick and running back Frank Gore had the 49ers playing for the second seed and a first-round bye, but ran into a 10-5 Seahawks team who won three in a row and put up 58 over the Cardinals and 50 on the Buffalo Bills.
Then-rookie Seahawks quarterback Russell Wilson threw four touchdown passes, and running back Marshawn Lynch ran for 111 yards with a rushing touchdown and a touchdown reception in the rout of the eventual NFC Champions.
In this span, the Seahawks would beat the 49ers by double digits in six of seven seasons.
Though he was sidelined with an Achilles injury, San Francisco 49ers quarterback Jimmy Garoppolo was on the sideline last season for the 43-16 loss to the Seahawks.
Garoppolo said the atmosphere was hostile and loud.
"Crowd's chirping at you and everything on the sideline," Garoppolo said this week. "That's what makes football great, especially this time of year. You couldn't ask for anything more in December."
The Seahawks fanbase, which is known as the "12th Man," made Century Link Field one the loudest stadiums in the NFL and held the record for the loudest in the league with 137.6 decibels during a 2013 Monday night game against the New Orleans Saints.
The record was broken the following year at Arrowhead Stadium on a 2014 Monday night game when the crowd noise reached 142.2 decibels as the Kansas City Chiefs hosted the New England Patriots.
San Francisco 49ers head coach Kyle Shanahan said the main thing to know about Seattle is how loud it is.
"Everyone's played in loud stadiums, and that's usually the loudest," Shanahan said. "You're not going to be able to hear. What I can say to Jimmy is it'll be exactly like New Orleans was. I've been in New Orleans a bunch, but New Orleans was different. The last time we were there was the loudest I've ever been anywhere. Last time in New Orleans was tied with how Seattle is, so it'll be very similar to that, and I thought he handled himself well there, and I expect him to do the same thing in Seattle."
The last time the 49ers won at the Seahawks' home stadium, then called Quest Field, was on December 24, 2011, which was a 19-17 victory.
This same season, the 49ers finished with a 13-3 record and a second seed in the NFC.
In the Divisional round of the playoffs, Alex Smith threw a last-second 14-yard touchdown pass to Vernon Davis, which is known as "The Catch III," for a 36-32 victory over the New Orleans Saints.
The Niners' playoff run ended the following week in the NFC Championship game with a 17-20 overtime loss to the New York Giants.
Garoppolo said division games are always significant.
"Whether you were born into this team or got traded, whatever it is, drafted here," Garoppolo said. I think the level of intensity of these games is real. If you don't know that going into it, you're going to be in a bad spot. The last time we played these guys, it was Monday night here, and that was a hell of an atmosphere, too. You kind of know what you're getting into."
Shanahan said the team is excited to play the Seahawks and go for the division title.
"This is definitely a week you don't have to try at all to get your team up for the game," Shanahan said. "It'll be the same thing for them. Just the times I've been in this situation in the past, it's extremely fun to coach. You have everyone's attention; everyone is completely into it. No stone goes unturned by anyone. You don't have to push anyone on that. Everyone's going to be locked in, and that's all you can do. That's what you try to tell guys. You're going to be excited to play; you're going to work as hard as you can, that's all you can control. Be prepared and then just cut it loose."
A win in Seattle would not only break a streak but would give the 49ers a first-round bye and home-field advantage throughout the playoffs.
This victory would also give this team the confidence to go anywhere and beat any team.
This victory would allow the Niners to get players like defensive end Dee Ford healthy and not travel to places such as Lambeau Field, The Mercedes-Benz Superdome, Lincoln Financial Field, or possibly going back to the House of Horrors known as "The Clink."