The men in black are massing.

Sony Pictures is moving forward on MIB 3, the third movie in its sci-comedy franchise.

Tropic Thunder writer Etan Cohen is penning the script, and Barry Sonnenfeld, who directed the first two films, is said to be attached to the new installment, though there is no formal deal or offer as yet.

The studio is eyeing a 2010 start date for the production.

The X factor remains Will Smith. The A-lister, who starred with Tommy Lee Jones in the first two Men in Black films, has not committed to the project, though in recent days the buzz in development circles has been that he is interested in returning. Smith does not have a pending movie project lined up.

Jones' involvement is uncertain.

Sony announced in April that it would bring back the tale of covert, pseudonymous agents who stalk the earth fighting disguised aliens, zapping beasts and memories as they go.

MIB has proved to be one of the most successful comedy franchises of all time. The two pictures -- which came out in 1997 and 2002 -- combined to earn nearly $1.1 billion worldwide.

The addition of Cohen, who is said to be deep into his draft, signifies the studio's intention to maintain the franchise's top-tier status. The writer is a hot commodity, penning the sequel to Madagascar and the Will Ferrell-toplined Sherlock Holmes project, as well as Thunder.

Ed Solomon wrote the script for the first Men in Black, and Robert Gordon and Barry Fanaro penned the second film.

Sonnenfeld has been concentrating on TV of late, inking a deal with ABC and ABC studios, and executive producing the dark comedy series Pushing Daisies. His last feature was the Robin Williams-starring RV.