The Dirty Underground [Jerome Valeska] (sequel to YDMC)

It's been a year since Rumer and Jerome reunited in Arkham. Theo is dead, Tabitha's dead, they have friends on the outside, and Penguin and Nygma have failed in finding Barbara.
The GCPD has one last hope for catching 'Bloodthirsty Barbara', Rumer and Jerome. The two are promised their freedom if they can bring in Barbara and her allies.
Bloodthirsty themselves, the two agree, ready to chip away pawns to have a kick at Barbara.