Complex sentence: In the episode "Chasing Ghosts," Tony Stark and Whitney Stane believe that Obadiah hired an assassin named Ghost to kill Stark, but it turns out that Obadiah was actually tipping off the FBI about the assassination attempt.
Split into simpler sentences: In the episode "Chasing Ghosts," it was believed by Tony and Whitney that Obadiah hired Ghost to assassinate Tony. It turned out that Obadiah was actually tipping off the FBI about the assassination attempt.