Heidi Klum chatted about season 21 of "Project Runway" on "GMA" and revealed a hint about her Halloween costume this year.

The supermodel and executive producer Michael Rucker discuss their homecomings to the series, the dynamic cast and why Christian Siriano remained as the designer’s mentor with the network shift.

The supermodel, now back as host of 'Project Runway' for its newest season, wore a flowing chartreuse dress with a high turtleneck and long sleeves. The piece featured an airy silhouette with feathered cuffs. Her beauty game was just as polished, including soft waves parted down the center, glowing skin, winged eyeliner, and glossy lips.