Last Christmas, Charlie Barnett, an Emmy-nominated composer of film and television, gave his annual Christmas party at home for 250 of his closest friends, neighbors and acquaintances.

"I take the holidays seriously, and I have been doing this for 20 years," he explained. "It is a big, happy mess, and anyone who wants to sing comes close to the piano, [the group] spreading out through three rooms. It's quite a joyful noise, and I love doing it."

Danny Schwartz of the Hamilton club was a guest at the party and confronted Barnett with a request to repeat this holiday sing-song the following year at his venue. Now, this master of improvisation has put it all together in Sunday's Very Special Holiday Hamilton Brunch, taking place at the District's own Hamilton.

"I have no idea what it's going to feel like to the audience; hopefully, it'll come across as somewhere between me and Perry Como combined trying to get the audience to sing along to songs they already know," he continued. "I mean, who doesn't know most of the Christmas carols?"

Very Special Holiday Hamilton Brunch with Charlie Barnett
Where: The Hamilton, 600 14th St. NW
When: 10:30 a.m. and 1 p.m. Sunday
Info: $30; 202-787-1000;

Barnett and his jazz band, Chaise Lounge, have performed often at the Hamilton before and have done very well there. Sunday's format will, no doubt, be much of the same in that he has invited his bass player from the band, Pete Ostle, and guitar player Jerry Lynn.

"It's a big room to play on just a piano," Barnett said. "I want to be able to get up and not be chained to the bench ... then I can conduct and get everybody involved. I have a feeling this show is going to be something between a pep rally and a chorus of hopefuls."

Through it all, Barnett wants his audience to have fun, to go with it and enjoy the spontaneity. Much like his Christmas home parties, he wants the group loose and comfortable. And so he is quick to reassure those who plan on joining him in this offbeat merriment.

"Even though I have a world-class closet full of sharkskin suits, I will be wearing a spectacular cardigan for this show," he said.