Per Collider, he said he has three finished scripts that he is deciding between for his next film. "If the one that I think will happen happens, it's something that started fifteen years ago. I wanted to do it fifteen years ago. We started. We couldn't do it. It went completely in a beautiful roundabout way and came back to me."
When he was asked if the project would be recognizable once it's announced, he replied, "Oh yes, yes, yes, trust me. And those are projects that are really great associations, world creation projects. Big projects."
Collider speculates that the next big project is del Toro's adaptation of the Alexandre Dumas novel The Count of Monte Cristo, which has been given the working title The Left Hand of Darkness.
Regarding del Toro's Frankenstein project, the director said, "I'm presenting the storyline to Universal...but I think that I wanna be if possible shooting in May next year. So I need something that's ready to go into pre-production immediately."
Regarding Hellboy III, del Toro said, "The Hellboy screenplays are not quick to write. For whatever reason, they end up being very complicated to write. And I don't know why, so if we went and did Hellboy it would need to be the next movie after this one or whatever, but I don't know yet."
Per Bloody Disgusting, he also explained why his HP Lovecraft adaptation, At the Mountains of Madness, hasn't come to fruition, and why it may never.
"I'm like a broken record, I'd love to be doing Mountains of Madness. But still, even now, it's very difficult for the studios to take the step of doing an R-rated, tentpole movie with a tough ending, no love story, set in period from a writer...[who has] a readership as big as any best-seller, but it's [tough] to quantify because his works are in the public domain. But...they have been reprinted for so many decades and they have captured the imagination of so many filmmakers is how powerful this guys is. But since it doesn't look like I can do Mountains of Madness, I have now [narrowed down] the projects that I am interested in to three."
Del Toro added that he hopes to make his next project announcement at Comic-Con in July.