Tony winners Andrea Martin and Nathan Lane will join host Andy Cohen for the 11 PM ET broadcast.
Stage and screen star Martin is the author of the newly released "Andrea Martin’s Lady Parts." Lane is back on Broadway in Terrence McNally's It's Only a Play.
"Watch What Happens: Live," according to press notes, is "Bravo's late-night, interactive talk show that features guests from the world of entertainment, politics, and pop culture. Hosted by Andy Cohen, the series includes lively debates on everything from fashion, the latest on everyone's favorite Bravolebrities, and what celebrity is making headlines that week."