The actor and filmmaker will write and direct the twisted comedy, reports Deadline.
The film centres around a former child star, who is now a struggling agent.
When he meets a brilliant 13-year-old acting prodigy (played by newcomer Saxon Sharbino) he attempts to close a deal while managing her drunk and volatile father.
The cast features Amanda Peet, Paul Sparks, Felicity Huffman, Allison Janney, William H Macy, Molly Shannon, Niecy Nash and Sam Rockwell.
Best known for his acting roles as Agent Coulson in Marvel Studios' movies, Gregg also made his directorial debut on a feature film with 2008's Choke, which also starred Rockwell.
Principal photography for Trust Me began on September 26.