A lone man embarks on a music-listening journey, only to discover that the real journey was. the friends he made along the way. 

Boris is a spy from the fictional nation of Pottsylvania, and takes orders from the strongman known as Fearless Leader (and occasionally the rarely seen Mr. Big). Boris' missions range from trying to steal a secret rocket fuel formula to eliminating all television from the United States as part of Pottsylvania's various attempts to seize power. Boris, who is thoroughly dedicated to (and takes delight in) all manners of nefarious deeds, would also sometimes engage in his own schemes, such as starting his own organized crime gang and hiring himself out as a professional executioner, and frequently conspires schemes simply to get rich (such as by posing as a Hollywood director to bilk Bullwinkle out of his life savings in "The Last Angry Moose" or usurping Santa Claus by taking advantage of a freak polar drift in "Topsy Turvy World"). Separately from the television series, a commercial for the Rocky and Bullwinkle Show featuring Boris established that he was an active member of Local 12 of the Villains, Thieves, and Scoundrels Union.[8] During this commercial, Boris also claims to be "the world's greatest nogoodnik". Boris is also quite proud of the fact that the nicest thing Fearless Leader ever did for him was sending a picture of himself to Boris inscribed "Drop Dead — Fearless Leader".

According to the Rialto Theater's "Moosebill" for "Downhill: The Musical" (a special table of contents insert created for the DVD box set Rocky and Bullwinkle & Friends, The Third Season), Boris was educated in the Pottsylvania public schools before taking a scoundrelship to U.S.C. (the University of Safe Cracking), from which he graduated magna cum louse. He has a cast-iron stomach; and because of it was one of only three survivors of the ruling clique of Pottsylvania, the other two being his superiors Fearless Leader and Mister Big. Boris enjoys light reading; his favorite book is an anthology of fiendish plans called the Fireside Crook Book. He is also a charter member of the Van Gogh Society, a Pottsylvanian club whose members collect human ears.

Early in the series, Boris was taller and had red eyes. After the first episodes, he changed to his normal height, but still retained the red eyes until a few episodes afterwards. Humorously, they changed from red to white after he had woken up from a long slumber, as if the redness was caused by sleep deprivation.

Boris is nearly always accompanied by his fellow criminal, Natasha Fatale. The first time he appeared without her was in the story arc, "Buried Treasure". The first story arc where neither appeared was "The Three Moosketeers".

Usually, Boris' misdeeds are thwarted by Rocky the Flying Squirrel and Bullwinkle the Moose. Boris's attempts at killing "moose and squirrel" (as he refers to them) also always end in failure, usually by his own scheme backfiring on him. "Of course, I've got plan!" he says. "I've always got plan! They don't ever work, but I've always got one!" As Boris expresses his plight in one promo: "I send in lady spy with package which is really bomb. Door gets locked, she can't get out, who gets blown up? Me!"[9]

Boris appeared in all but three Rocky and Bullwinkle storylines: The Three Moosketeers, The Ruby Yacht, and Mucho Loma. Boris often appeared in segments of Bullwinkle's Corner, Mr. Know-It-All, and The Rocky and Bullwinkle Fan Club.

Boris Blumbo Music Hour

Written and performed by Kara Avery
Guitar, bass, drums, synthesizers and programming by Chris Dacanay
Creative oversight and percussion by Joseph Fusselman