Field trip time!

Sarah Jessica Parker and her husband Matthew Broderick stepped out on Thursday to attend the opening night of Broadway’s Hello, Dolly! with Andy Cohen -- and to their sweet surprise they went unnoticed!

“C train to the opening of Hello Dolly! AND I CAN'T WAIT! #GayChristmas,” the Watch What Happens Live host captioned his Instagram post, showing how no one on the train noticed them.

WATCH: Sarah Jessica Parker Gifts Kim Kardashian With Custom Suede Shoes and a Handwritten Note

Parker also took to Instagram to document the night, sharing a funny video of Cohen and Broderick dancing while waiting for the train.

“Act 1,” the Divorce star captioned the cute snap.

WATCH: Naomi Watts Hilariously Sneaks a Photo of a Fan Snapping Her on NYC Subway -- See the Pics!

But, not all celebrities go unnoticed. See how Naomi Watts cleverly reacted when she caught a fan taking pictures of her in the video below.