It’s like the old saying: Sometimes, it’s not enough to stab a guy; you also have to blow him up. At least, that seems to be the thought in “Grand Deceptions,” a confusing late Columbo set at a military think tank which also trains mercenaries on the side. Oh, and illegally runs arms. When he’s not busy shaking yarrow sticks, Frank Brailey, the think tank’s head, diverts millions of dollars from the foundation in the off hours he’s not busy cheating with the wife of his boss, an esteemed retired general. When one of Brailey’s subordinates catches wind of his many, many irons in the fire, that’s when the stab/blowup twofer happens. Call in Lt. Columbo who observes the chain of evidence one moment, while straight-up stealing documents the next. All in all, its a weird mix that never quite gets there and the panel is left wondering exactly who the heck this was for and what it was trying to say. Guests Jennifer Wright (Get Well Soon: History’s Worst Plagues and the Heroes Who Fought Them) and Daniel Kibblesmith (Late Show with Stephen Colbert) return for this, the 50th show.