Charlie Sheen is gearing up for a Hollywood comeback ... hinting to us he has something else in the works after pulling together his memoir and a new docuseries, back to back.

We caught up with the actor Tuesday morning in NYC, where he was practically on cloud nine while discussing all the positive feedback he's received for his new book -- "The Book of Sheen" -- and his Netflix doc, "aka Charlie Sheen."

Per Charlie, he feels a lot better having everything out in the open ... including all the details about his past wild love life.

However, it seems the "Two and a Half Men" alum is looking to keep the momentum going amid his return to the spotlight. Watch the vid, he promised he was set to do something he hasn't done in "a long time."

While Charlie wouldn't confirm or deny a new acting project, he made it clear he's open to any and all opportunities.

He added ... "Whatever's supposed to happen next is what will happen."

The actor has taken a noticeable step back from the limelight since getting sober in 2017. He's accepted only a handful of acting roles, including a guest stint on the HBO Max comedy, "Bookie."

He's slated next to appear in "Ramble On," a new project from "Entourage" creator Doug Ellin. Though, there's no word on whether that show will even drop ... it's been stuck in limbo for a while now.

So, we guess we'll just have to wait and see what's next for Charlie.