Mike the Angel--M. R. Gabriel, Power Design--has devised the power plant that is to propel the space ship Branchell to its secret destination, complete with its unusual cargo. And, as a reserve officer in the Space Patrol, Mike is a logical replacement for the craft's unavoidably detained engineering officer.

But once into space, the Branchell becomes the scene of some frightening events--the medical officer is murdered, and Snookums appears to be the culprit. Mike the Angel indulges himself in a bit of sleuthing, and the facts he turns up lead to a most unusual climax.

The kids who tried to jump Mike the Angel were bright enough in a lot of ways, but they made a bad mistake when they tangled with Mike the Angel.

They'd done their preliminary work well enough. They had cased the job thoroughly, and they had built the equipment to take care of it. Their mistake was not in their planning; it was in not taking Mike the Angel into account.

There is a section of New York's Manhattan Island, down on the lower West Side, that has been known, for over a century, as "Radio Row." All through this section are stores, large and small, where every kind of electronic and sub-electronic device can be bought, ordered, or designed to order. There is even an old antique shop, known as Ye Quainte Olde Elecktronicks Shoppe, where you can buy such oddities as vacuum-tube FM radios and twenty-four-inch cathode-ray television sets. And, if you want them, transmitters to match, so you can watch the antiques work.

Mike the Angel had an uptown office in the heart of the business district, near West 112th Street-a very posh suite of rooms on the fiftieth floor of the half-mile-high Timmins Building, overlooking the two-hundred-year-old Gothic edifice of the Cathedral of St. John the Divine. The glowing sign on the door of the suite said, very simply:

M. R. GABRIEL
POWER DESIGN

But, once or twice a week, Mike the Angel liked to take off and prowl around Radio Row, just shopping around. Usually, he didn't work too late, but, on this particular afternoon, he-d been in his office until after six o'clock, working on some papers for the Interstellar Commission. So, by the time he got down to Radio Row, the only shop left open was Harry MacDougal's.

That didn-t matter much to Mike the Angel, since Harry's was the place he had intended to go, anyway. Harry MacDougal's establishment was hardly more than a hole in the wall-a narrow, long hallway between two larger stores. Although not a specialist, like the proprietor of Ye Quainte Olde Elecktronicks Shoppe, Harry did carry equipment of every vintage and every make. If you wanted something that hadn't been manufactured in decades, and perhaps never made in quantity, Harry's was the place to go. The walls were lined with bins, all unlabeled, filled helter-skelter with every imaginable kind of gadget, most of which would have been hard to recognize unless you were both an expert and a historian.

Old Harry didn't need labels or a system. He was a small, lean, bony, sharp-nosed Scot who had fled Scotland during the Panic of '37, landed in New York, and stopped. He solemnly declared that he had never been west of the Hudson River nor north of 181st Street in the more than fifty years he had been in the country. He had a mind like that of a robot filing cabinet.