Two execs who traveled to London to be grilled by the US Securities and Exchange Commission turned the business trip into a “bacchanalian adventure” — blowing $12,000 on first-class plane tickets, staying in a five-star hotel and sneaking off to Madrid for a two-day trip, new court papers say.

Glynn Fisher and Taylor Housser, both principals at a defunct securities brokerage firm in Panama, took the jaunt to the UK in order to be deposed by feds in a pending stock-fraud case against them.

The SEC agreed to reimburse the company for “reasonable commercial” expenses, but the duo racked up a $17,000 bill during their trip — including the airfare, four-night stay at the $700-per-night Lanesborough hotel and more than $1,000 bar tab.

Fisher and Housser also indulged in an $85 bottle of Cabernet and $100 bottle of Spanish wine and bought tickets to tour St. Paul’s Cathedral — all on the SEC’s dime.

Manhattan federal court Judge William Pauley ordered the agency to pay back only “reasonable costs.”