An annual sign that summer is officially over: Saturday’s lavish “Welcome Back” bash hosted by developers Jane and Calvin Cafritz in the back yard of their Georgetown home, complete with opera singers, a DJ — and, this year, an ambulance.

Jane and Calvin Cafritz greet guests at their end-of-summer party Saturday night. (Tony Powell)

The decade-old seen-and-be-seen party is the first chance for Washington’s society A-listers — politicians, diplomats, millionaires and other big shots (“You know who you are,” Calvin told the crowd) to reconnect and trade vacation tales. Mayoral candidate Jack Evans put the schmooze on his affluent neighbors. (Campaigning? “Always. All the time,” he said with a grin.) Newly minted Sen. Ed Markey accepted congratulations from longtime pals.

And former ambassador Walter Cutler turned out despite a nasty stomach bug, which proved to be his undoing: In the crush of guests, he collapsed. But VIP help was on the way: Anthony Fauci of the NIH, Howard oncologist Lasalle Leffall and other D.C. top docs tended to Cutler until an ambulance whisked him to the hospital. “It was amazing,” said Didi Cutler from her home, where her husband was “fine” and resting comfortably Sunday.

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