There’s two times in IWTV that Lestat says he just wanted to talk to Louis post-swamping.

1. “There’s something I must tell you… about that night in the swamp.“

^Lestat says this to Louis in Paris, at the Theatre des Vampires, re: smtg Lestat had wanted to tell Louis the night Louis and Claudia put him in the swamp, seemingly dead. 

Neither of them ever bring it up again, but my guess would be that it had smtg to do with the feeling Louis had when he put Lestat in the swamp. In the book, he walks into the muck w/ Lestat’s body, going far from shore, and feels a pulling, like he should go down with the body:

“I felt a pull suddenly, as if some force were urging me to go down with him, to descend into the dark water and never come back. It was so distinct and so strong that it made the articulation of voices seem only a murmur by comparison. It spoke without language, saying, `You know what you must do. Come down into the darkness. Let it all go away.‘”

Being maker and fledgling, they technically cannot read eachother’s thoughts, so maybe, in this extremely emotional moment, Lestat was able to pierce that veil to cry out for Louis in the only way he could ;A; Or maybe it was just Louis feeling guilty about, idk, helping kill his own maker!!!

Hit the jump for more, cut for length.

2. “ ‘I wanted to talk to you so much,’ he said. `That night I came home in the Rue Royale I only wanted to talk to you!’… `I went to Paris after you…’ ” 

^At the end of IWTV, when Louis finds a very decrepit (but not dying, Louis says “dying” but it’s emotionally dying, not physically) Lestat, Lestat insists he just wanted to talk to Louis the night he dragged his soggy butt out of the swamp and back to the Rue Royale, but it seems to refer to what he said in Paris, smtg about the swamp.

We don’t even know if this scene in IWTV actually happened, bc Lestat denies it in later books. We have a pile of unreliable narrators.

[^What a bittersweet moment in movie!IWTV, that “final” meeting before Louis goes to SF to find some cute guy to tell his life story to.]

Based on the fact that Lestat wrote an entire book in response to IWTV, he most likely wanted to tell Louis EVERY SINGLE THING that was in that book. It’s Lestat’s backstory, everything else he couldn’t tell Louis during the 65ish years they were together in NOLA, and most importantly, WHY he couldn’t tell him any of those things.