Watch David Letterman Roast Donald Trump With a Top 10 List

John Paul Filo/CBS

Letterman said he "made the biggest mistake of [his] life" in regards to retiring before finding out about Trump's presidential run.

David Letterman gave up his retirement for one evening and joined Steve Martin and Martin Short former Father of the Bride co-stars onstage in San Antonio, where Letterman dedicated time to roasting Donald Trump with one of his top 10 lists.

"I am so happy to be out of the house," Letterman told audiences, Mediaite first reported. He joked that the trio met "back in Hollywood at a Scientology mixer."

The former late-night host said he has "no regrets" about retiring because "he'll make actual friends," but he added that his contentment went away a few days ago — when Trump announced his run for a presidential ticket.

"I have made the biggest mistake of my life," he joked about exiting the Late Show.

Letterman proceeded to pat his coat pocket, from which he pulled out an envelope and added, "Every suit I own comes with a top 10 list." This particular list was titled: "Interesting facts about Donald Trump."

He started with No. 10: "That thing on his head was the gopher in Caddyshack."

Letterman made his way down the list, joking about subjects including: Trump's hair, his intimate life, "building a wall around the thing on his head," immigration and Trump's cologne adding 10 pounds to his weight.

Watch the video below.