Katy Perry Films 'SNL,' Matt Damon In Homeless Disguise (PHOTOS)

At first glance, it's Katy Perry who looks like she made the biggest transformation in these photos, what with her light brown hair and Old Navy-inspired garb. But take a look at the guy standing in front of Perry and Andy Samberg, shoving some pizza in his face?

Recognize him?

Under all that hair and bedraggled clothing, it's Matt Damon!

The "We Bought A Zoo" star looks to be guesting in a "Saturday Night Live" digital short starring Samberg and Perry, who is hosting the show tomorrow night. Unlike his clean cut dad look in the Cameron Crowe-directed family movie, Damon is delightfully unkempt here.

PHOTOS (all via Splash):