It wasn’t when I came home from work. It was while I was home which made it even more shocking. It was my fortieth birthday and my wife and I were going out for dinner with our best friends , a couple. I was waiting for my wife to get ready before leaving to pick up our friends when she yells from upstairs that she lost a contact. I raced upstairs to our bedroom where she was on her hands and knees looking I joined her, and after about five minutes she found it. We walked downstairs and she says , let’s take a picture in the living room, where about forty people shout surprise. Also there are a staff of caterers and a buffet table . My wife had planned it to the second with synchronized watches, and everyone parking down the street, and all coming up at once. My boss, a dear friend, had difficulty walking due to a wound suffered in France during WW2, and being the sport he was, agreed to be carried along by two of my bigger friends. I have never been so surprised in my life . I mean , I had never left the house! I’m 77 now, and she and I still play tennis every day together, and well, are still husband and wife if you know what I mean. We’ve been married almost 54 years.
Edit. My son insists that it was my 35th, not my 40th birthday, so I am editing the answer to get him off my back. Happy, Josh?

Additional edit. When I read this to my wife, she pointed out that I made a mistake. There were NO caterers. She did all the cooking and put the food in our neighbor’s freezer before the party. She hired waiters, but she did the cooking. She still amazes me.