The two comedy legends were at the Pleasantville Diner on Wednesday filming an episode of Seinfeld's online show "Comedians In Cars Getting Coffee."
The show follows Seinfeld and another celebrity as they take one of Seinfeld's cars to a coffee shop to chat.
Joanne Ellis of the Pleasantville Diner said they were given a week's notice about the comedians' appearance and said it was exciting.
"It's something different," Ellis said. "It makes the workday go by quicker."
Katie Mitts, a Pace University student, was at Starbucks studying when she and some friends saw a camera crew and then Seinfeld pull up in a red Mustang.
"We didn't believe it," Mitts said. "It's so cool."
They then saw someone with white hair and realized he was with Martin.
"That was the icing on top," Mitts said.
Though Mitts has never watched "Seinfeld," she said she loves two movies in which Martin starred: "Cheaper By The Dozen" and "Father of the Bride."
A production assistant said they got lost on the Saw Mill River Parkway for an hour driving to Pleasantville from New York City.
Martin had an egg salad sandwich while Seinfeld had a mozzarella omelette and both had ice cream for dessert. Martin said he would love to come back to the diner again, but on one condition.
"Just not with him," Martin said, pointing at Seinfeld.
To view "Comedians in Getting Cars Getting Coffee," visit www.crackle.com/comedians-in-cars-getting-coffee
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