In February 2021, the American professional wrestling promotion All Elite Wrestling (AEW) started a partnership with the Japanese promotion, New Japan Pro-Wrestling (NJPW), with Kenta being the first NJPW wrestler to appear on AEW's primary weekly television program, Wednesday Night Dynamite during the Beach Break special.

They were interrupted by AEW wrestler Adam Cole, who officially announced that a co-promoted event titled Forbidden Door would be held on June 26 at the United Center in Chicago, Illinois.

Forbidden Door featured professional wrestling matches that involved different wrestlers from pre-existing scripted feuds and storylines.

[9] On the June 1 episode of Dynamite, newly crowned AEW World Champion CM Punk called out his NJPW Forbidden Door opponent.

Instead of vacating the title, AEW president Tony Khan announced that they would crown an interim champion at Forbidden Door.

A battle royal was scheduled to open the June 8 episode of Dynamite, with the winner facing Jon Moxley, who was the number one ranked singles competitor, in the show's main event, and the winner of that match would be placed in the match to crown the interim AEW World Champion at Forbidden Door.

[10] It was then announced on AEW's social media that the winner of Hiroshi Tanahashi vs. Hirooki Goto at NJPW's Dominion 6.12 in Osaka-jo Hall would be the other competitor in the interim championship match at Forbidden Door.

[11] On the June 8 episode of Dynamite, Kyle O'Reilly won the Casino Battle Royale, but was defeated by Moxley in the main event, who advanced to Forbidden Door.

[13] On the June 8 episode of Dynamite, "Hangman" Adam Page wrestled his first match since losing the AEW World Championship to CM Punk at Double or Nothing, defeating David Finlay.

Page was interrupted by Adam Cole, who pointed out that Okada may not be champion by Forbidden Door due to his scheduled title defense against Jay White at Dominion 6.12 in Osaka-jo Hall.

[15] Page addressed the situation on the June 15 episode of Dynamite, and was once again interrupted by Cole, who also wanted to face White for the title.

[17] It was later announced that White would defend the title in a four-way match against Okada, Page, and Cole at Forbidden Door.

[21] On the May 25, episode of Dynamite, the United Empire's (UE) Great-O-Khan and Jeff Cobb interrupted a match for the ROH World Tag Team Championship between FTR (Cash Wheeler and Dax Harwood) and Roppongi Vice (Trent Baretta and Rocky Romero), attacking both teams.

[22] The following week, faction leader Will Ospreay made his surprise debut where, along with other UE stablemates Aaron Henare and Kyle Fletcher and Mark Davis of Aussie Open, they attacked Beretta and FTR.

Soon after, a singles match between both men was scheduled for Forbidden Door for Ospreay's IWGP United States Heavyweight Championship.

[27] Since the announcement of Forbidden Door, Zack Sabre Jr. had continuously called out in post-match interviews, challenging "The American Dragon" Bryan Danielson to find out who the best technical wrestler was.

[30] Following their defeat in the Anarchy in the Arena match at Double or Nothing, Eddie Kingston along with Santana and Ortiz continued to feud with the Jericho Appreciation Society (JAS).

Later in the night, Jericho interrupted the face-to-face confrontation between Moxley and Tanahashi, and both men were immediately attacked by Suzuki-gun members Lance Archer and El Desperado, despite additional help from Wheeler Yuta.

Allin and Sting accepted their challenge with their partners being Los Ingobernables de Japón's Hiromu Takahashi and Shingo Takagi.

Hobbs stated that Strickland and Lee think they are Shaquille O'Neal and Kobe Bryant, and then compared himself and Starks to Michael Jordan and Scottie Pippen.

Before the match began, Danhausen appeared on the screen and introduced a new "Ass Boys" theme, which caused Austin and Colten to run to the back.

[39] After that was the inaugural AEW All-Atlantic Championship four-way match between Pac, Clark Connors, Miro, and Malakai Black.

[39] In the sixth match, Will Ospreay (accompanied by Aussie Open) defended the IWGP United States Heavyweight Championship against Orange Cassidy.

Claudio Castagnoli made his unannounced AEW debut as Sabre Jr.'s opponent and also became the newest member of Blackpool Combat Club.

Castagnoli broke free and later hit Sabre Jr. with an uppercut and a lariat and then performed the Ricola Bomb on the latter to win the match.

Moxley applied the rear naked choke submission, who later released the hold and executed the Paradigm Shift on Tanahashi to become the interim AEW World Champion.

Jake Hager, Matt Menard, Angelo Parker, and Sammy Guevara ran out to help Jericho and Garcia.

Additionally, due to Bryan Danielson's injury preventing him from participating in Blood and Guts, Claudio Castagnoli took his place in the match.

The match resulted in the Blackpool Combat Club, Kingston, Santana, and Ortiz defeating the Jericho Appreciation Society.

[40] Due to Hirooki Goto and YOSHI-HASHI's win over The Factory, The Young Bucks challenged them to a match on the Rampage special episode Royal Rampage for an opportunity at the Bucks' AEW World Tag Team Championship, however at the show Goto and Yoshi-Hashi were defeated.