Richard Dennis was startled when he heard someone banging on his backdoor around 11:30 p.m. Tuesday, authorities say. The 61-year-old gripped a gun as he stepped outside his home in Gulf Breeze, Fla. When he saw a person jump out of the bushes, he pulled the trigger.

Only then did Dennis realize who the person was: his son-in-law.

Christopher Bergan had flown 4,500 miles from Norway, where he and his wife live, to get to the Florida Panhandle. It was supposed to be a birthday surprise for Dennis, who was turning 62 the next day. Instead, it was a tragedy: The bullet hit Bergan “straight in the heart,” Santa Rosa County Sheriff Bob Johnson said, killing the 37-year-old instantly.