TOM HANKS is Our Greatest Living Actor. This is nowhere more evident than in Sir Hanks’ latest and most triumphant role, a man of international intrigue, dashing panache, and unparalleled heroism—David S. Pumpkins, the character Lord Thomas of Hanks brilliantly portrayed on last week’s episode of Saturday Night Live.

David S. Pumpkins does not appear in Inferno.

Instead, we get Robert Langdon, the Harvard professor of “symbology” who appeared in two previous movies, The Da Vinci Code and Angels and Demons. All three are based on unfathomably popular books by Dan Brown, and four out of five Americans have done the following: bought a copy in an airport bookstore, read it to page 30, fallen asleep, and left it behind on the plane. Discarded copies of Brown’s literary oeuvre were the primary building material used in the construction of JFK’s giant, sparkling, new Terminal 4.

This new Langdon movie has the same conceit as the other two: Indiana Jones, but in loafers, and with fewer Nazis, and worse. Langdon is on the hunt for a virus that could kill half the world’s population, but he got bonked on the head and can’t remember anything. An English lady doctor (Felicity Jones, who’s about to be the most famous person on the planet in seven weeks) assists him as he looks for clues in the works of Botticelli and Dante.

It’s all totally fine until about two-thirds of the way through when the plot disintegrates in the favor of an unearned twist. And the climax is insultingly, infuriatingly bad: The virus, which the bad guys have put in a fucking plastic baggie in ankle deep water, must be prevented from being discharged by detonators, because actually releasing the virus would be too simple. Up ’til then, Inferno is the sort of half-crappy thing you might watch for free on an airplane. Just make sure you fall asleep before it’s over.