Detective Annual 5 is part of the Eclipso: The Darkness Within crossover running through the DC annuals in 1992. Alan Grant, John Wagner, Tom Mandrake, Jan Duursema and Rick Magyar are the creative team on this issue, which launches a storyline that runs through the various Batman annuals.
The Ventriloquist has been released from prison, and re-opened his old club, claiming to be going straight.
Batman is busy, stopping a robbery of ancient Egyptian artifacts. One of the pieces has a number of black diamonds hanging from it,one of which comes loose, and winds up in Batman’s possession. He brings it to police headquarters, where he winds up meeting with Bruce Gordon, who explains about Eclipso, and the diamonds’ power to either possess someone, or have them evoke an Eclipso.
The Ventriloquist has bugged all the tables in his club, so that he listen on the conversations of the hoodlums who dine there, and learns that the Joker’s men are waiting for their boss to lead them to a huge stash of money.
So the Ventriloquist and Scarface have their men grab the Joker first, forcing him to take them to his hideout, in a toy factory.
Commissioner Gordon hears of the Joker’s breakout, and his suppressed anger at the Joker’s shooting of Barbara causes him to evoke an Eclipso. Curiously, the diamond almost seems to draw Gordon to it.
Powered by Gordon’s anger, the Eclipso demon makes a beeline for the Joker, which also leads the police in the right direction. The Ventriloquist and Scarface are less then pleased with all the attention.
Batman and Gordon struggle with the Eclipso, while the Ventriloquist finds himself surrounded by the police, and surrenders.
Together, Batman and Gordon manage to take down the Eclipso demon, but the Joker used the distraction to get away.
The story continues in the Robin annual.