In the suit, filed today in federal court in L.A., the Massey brothers claim they met Bristol on "Dancing with the Stars" ... and developed the idea for a show in which the brothers help Palin meet the challenges of child rearing while adjusting to life in L.A.

In fact, the Masseys claim they had even picked out a name for the show -- "Helping Hands."

But according to the suit, a producer named David McKenzie hijacked the project, cut the Masseys out of the show and repackaged the program as "Bristol Palin: Life's a Tripp" for Lifetime.

The Masseys are demanding monetary compensation -- claiming they were not properly compensated or credited for creating the show.