For almost three weeks, a frequent flying feline traversed the United States in the hold of an airplane, after escaping its carrier.

When owners Guenther and Ingrid Koelbl flew from Phoenix to Philadelphia in April, they thought they had safely stowed their precious pet. In Houdini-like fashion though, “Billy” freed himself from his confines and missed his connecting flight to Munich. He was found 18 days later by mechanics in Manchester, N.H.

Weary and thinner, but generally unharmed, Billy was flown home in the passenger compartment in a box marked “Escape Artist.”

“The airline must be mouse-free by now,” Mrs. Koelbl said as she and the family were reunited with Billy at Munich airport. “The whole family is so happy. It’ll get an extra portion of whatever it wants to eat,” Mr. Koelbl said.

Leave it to a cat to make an elite-status mileage run.