BATMAN: BIRTH OF THE DEMON PART 1 Originally published as Son of the Demon, April 1977 & Bride of the Demon, January 1979. 

Ra’s al Ghul has spent half a millennium creating a criminal empire like no other. But when his preternaturally long life comes to an end, who will carry on as his successor? Having produced only daughters, Ra’s will stop at nothing to secure a male heir. Batman makes an unlikely ally for the Demon, but the Dark Knight embraces the partnership when al Ghul’s beautiful daughter Talia becomes pregnant with his child.

BATMAN #232 Originally published in June 1971. 

When Robin is drugged and kidnapped, it’s Bruce Wayne who receives the ransom demand. The Dark Knight’s secret identity has been deduced and there’s an unexpected intruder in the Batcave...