Batman: The Brave and the Bold#1(2009)

Moments after helping Aquaman defeat the man-android Carapax, Batman receives an emergency distress signal from London. There, the Caped Crusader finds a bizarre - and enormous - monster on the rampage, which proves more than a match for most of his gadgets. Fortunately, the monster's rampage has also alerted visiting businesswoman Karen Starr, the alter-ego of Power Girl. Pooling their efforts, Power Girl and Batman manage to restrain the monster while discovering its horrific secret: it is actually a grotesque fusion of hundreds of still-conscious civilians. Its "creator" is none other than Lex Luthor, who has sent it to raid the Tower of London for the Crown Jewels. Aided by Batman's deductive prowess, Power Girl uses her X-ray vision to find Luthor's hideout and immediately attacks. Luthor retaliates with a red sunlight generator, de-powering the rash Kryptonian, but still finds himself physically outmatched. Rallying, he tries to ambush Power Girl with a more conventional weapon, but is quickly subdued by Batman, who proceeds to chide Power Girl for acting without a plan. Though helpless, Luthor gloats his victory; his "composite creature" has already broken its restraints, and any attempt to relocate the Crown Jewels will only lead it on a wider rampage. The creature can only be stopped by reversing the "Concatenation Ray" that spawned it, and the ray's controls are password-protected. To his dismay, however, Batman and Power Girl quickly pinpoint the password as the one word he can never forget: Superman. With the controls unlocked, the ray's circuits are easily reversed, and the creature quickly turned back into hundreds of confused - but unharmed - civilians. The disgruntled Luthor is then taken into custody by the Yeoman Warders, while Batman and Power Girl are decorated by the Queen.