A Sick Plan - Batman: Arkham City (2011)

After Batman stopped him from escaping Arkham Asylum, the Joker sat alone in his padded cell, knowing something was wrong.

The first sign was an unusual, lump on his shoulder. He felt... tainted. Weeks went by and ten more unusual lumps appeared.

The TITAN had done something to him, something bad, something that wasn't funny at all.

The Joker was dying. He knew it and soon so would anyone who saw him. The last thing he needed was to appear weak before his rivals.
So one day at lunch, the Joker took a spoon and dug out another inmate's eyes, knowing this would get him solitary confinement. He could keep out of sights, at least until his transfer to Arkham City.

The Joker needed an escape plan, and on the night of his transfer, Harley Quinn provided one. Disguised as an Arkham guard, she overpowered the Joker's escorts and stole her puddin' away to a boat waiting on the island's quayside.

As the boat carrying the twisted pair sped off towards Gotham, it was joined by a second. A secret alarm placed by Batman had alerted him to the Joker's escape, and here he was in the Batboat, pursuing the fugitives.

They ignored his orders to stop, so Batman opened fire. As Harley steered the boat to shore, missiles ripped the hull to pieces.

They swam, the weakened Joker being pulled through the water by a distraught Harley, desperate to save her puddin'. She pulled the Joker out of the water to safety, somehow avoiding Batman's searchlight. She and the Joker sat there, gasping for breath when they suddenly realized where they were: Arkham City.