Trinity is a limited series comic book published by DC Comics in three issues. Matt Wagner, a famous American comic book writer and artist is the author of this graphic novel series and the pictures are also drawn by him.It was originally released in a comics form and later as a collection.

Very much appreciated by the readers, the story was later modified and published in its present form of a graphic novel.The series of this book mostly concentrates on the first meeting and friendship of the three superheroes; Batman, Superman and Wonder Woman.

Issue 1
Clark Kent was supposed to catch a train and go to work but he misses it intentionally. He hears a gunshot and discovers the driver to be killed. Kent turns into the Superman and saves the train from accident. He examines the bullet that killed the driver but doesn’t reach to any conclusion. Some shadowy figures were tracking his activity from distance. Some thieves are after kryptonite so they break into S.T.A.R. Labs but somebody stops them and leaves them hogtied. Everyone thinks it was superman who caught the thieves, but it’s Bruce (Batman), Superman’s old friend who happened to be there at that time. He is searching a cartel that can defeat the weapons of ‘the Purge’. At the same time in Antarctica, some other shadowy figures dig Bizarro – a villain out. Bruce informs Superman that the next target of the thieves is LexCorp disc.

Diana – the Wonder Woman knocks some shadowy fighters down and is invited to join ‘the Purge’. Kent comes to know that Purge group was after ‘Project Replica’ and finds it to be missing. Ra's al Ghul, a shadowy man makes Bizarro join the ‘Purge’. Superman meets the Batman in his cave where Batman tells him that the leader of the ‘Purge’ is Ra's al Ghul, an eco terrorist. Bizarro ransacks a nuclear sub and explodes missiles near Themyscira. Amazons think that Superman has done this so Wonder Woman comes to ask him about it. But, on discovering that it was done by Bizarro, they both take the invisible jet and go to acquire and destroy the sub in Sahara desert.  
In Sahara they discover an underground camp when immediately they are attacked by enemies. On noticing that Diana can deflect bullets, a unit of suicide bombers attacks them. Superman protects himself and Diana and then decides to ask for Batman’s help.

Issue 2
Batman captures some members of Purge but in the fight against Diana, he gets knocked down. Superman intervenes and introduces Batman to Diana as a friend. Now, Batman using Diana’s Lasso of Truth tries to make the Purges speak out truth. He is very brutal with them which makes Diana angry. Later Batman tells both of them about Ra's al Ghul and investigates about him more from the Purges. They come to know that there are missiles somewhere is Gotham. Wonder Woman leaves giving them one of her earrings which can be used as a transmitter as well and goes to Lazarus Pit to meet Ra's.

She doesn’t reveal her real identity. On this end Batman and Superman discover that there are half a dozen missiles and Ra’s can use them and destroy the communication system of the whole world. Wonder Woman discovers that missiles are kept ready, so she reveals her identity and fights with Bizarro who breaks her Lasso of Truth and defeats her. In Bulgaria at Silo, Superman successfully destroys a missile. But Ra’s says that another missile will destroy Gotham and there is one more for Superman to worry about. Diana is captured and Bizarro is about to kill her but at the same time Batman appears there and wounds him. He also defeats Ra’s in a fight, but sudden arrival of Ubu surprises Batman and Ra’s escapes. Some more fights are followed and Batman destroys the remaining missiles. But , Diana gets stabbed and Batman has to save her. Superman also comes there and three of them leave the Lazarus Pit.

Issue 3
Wonder Woman goes back to Themyscira; where; after some days both Batman and Superman go to meet her. Diana has just taken bath when Batman sees her. She is looking very beautiful so Batman is turned on and he kisses her. Diana is surprised but all of a sudden Batman is surrounded by Amazon soldiers. They are about to attack him when Superman intervenes. Soldiers are sent back and the trinity discusses the issue of Ra’s and the Purge. They decide that Superman will go to find Bizarro. They come to know that Ra’s is searching for a new place to make his head quarters and he has made friends with rogue Amazons from Bana-Mighdall. The Trinity guesses that Themyscira can possibly be Ra’s target for it. Superman finds out that Bizarro is at headquarters of Ra’s. He reaches there and fights with Bizarro. He buries Bizarro when Ra’s tells him about the two airplanes he is going to destroy in Metropolis. Superman rushes to the city and makes the planes crash in a lake. Here, Ra’s and Bizarro prepare their armies and attack Themyscira. Amazons also get ready for the battle.

Batman and Wonder Woman appear there and there are two combats – Batman - Bizarro and Diana - Ra’s. Artemis was helping Ra’s earlier but when it came to actual battle, she can’t fight against her own Amazons so, she turns against Ra’s. Superman comes and he cripples all the enemy helicopters. Wonder Woman defeats Ra’s and she helps Batman against Bizarro. Superman comes and defeats Bizarro. The war ends with the victory of the Trinity. The enemies are sent to the bottom of water, but Batman known that Ra’s will come back as he has always done. Ra’s body is taken away by his daughter and Artemis returns home after spending few  months at Paradise Island. The Trinity – Batman, Superman and Wonder Woman swear that they will be friends forever.