Batman: The Animated Series S01E57 - The Demon's Quest

When Robin is mysteriously abducted from his college campus, Batman begins a fruitless search... until he is astounded by the sudden appearance in the Batcave of Ra's al Ghul. Ra's quickly reveals that his daughter, Talia, has been abducted under circumstances similar to Robin's, suggesting that the same people are responsible. So begins an uneasy truce between Batman and 'The Demon'.