The annual charitable event is mischievously known as Spookstock. While many Washington insiders, let alone the public, haven’t heard of it, the gala has become a centerpiece for the capital region’s tightknit intelligence and military special operations communities.

“I’ve done my share of formal events and black dress nights. This is a lot more fun,” said retired Maj. Gen. Clay Hutmacher, the former director of operations for U.S. Special Operations Command. “It’s very casual. If you want to show up in a Def Leppard T-shirt, that’s fine.”

Now in its seventh year, Spookstock has raised millions for the CIA Officers Memorial Foundation and the Special Operations Warrior Foundation, which look after the families of CIA officers and special operations forces killed in the field. Last year, after expenses, each charity received about $400,000, according to Spookstock board member Mark Kelton.

The event is essentially fueled by defense contractors and mainstays of the military-industrial complex that pay big money for a table or a balcony box.