Tragedy. Starring Hailee Steinfeld and Douglas Booth. Directed by Carlo Carlei. (PG-13. 118 minutes.)

Viewers who go into "Romeo and Juliet" cold may be forgiven for coming away thinking Shakespeare was a really lousy writer. After all, this latest screen version has lines that go thud every minute, such as "We shall take action when we may and strike while the iron is hot!" Or this novel gem: "The best intentions pave the way to hell." Or this botch: "The prince's kindness is a golden ax that cuts my head off."

But Shakespeare didn't write those lines. Julian Fellowes ("Downton Abbey") did, and what he does to Shakespeare in this film, no writer should do to any writer - not even to Julian Fellowes. He capriciously rewrites dialogue, invariably replacing four concise words with 10 clumsy ones. He takes funny scenes and makes them labored and turns romantic scenes passionless. He changes character motivations, adds new scenes that are dumb and indulges in the worst aping of Shakespeare, with no feeling for the spirit or music of the original. Rarely do two lines go by without Fellowes changing something, always for the worse.

Thus, Shakespeare's line, spoken by Romeo, "All these woes shall serve for sweet discourses in our time to come," becomes, as rewritten by Fellowes, "And we shall smile to think of all these troubles in the past." Even Shakespeare's "rich jewel" becomes a "fine jewel" as rewritten by Fellowes. Anything to dim the language just a bit.

The result is an adaptation representing the worst of both worlds, neither authentic Shakespeare nor a wholesale update of the language, but rather mangled Shakespeare mixed with stilted, clumsy fake Shakespeare - a lifeless fake that will put many off of the original for the rest of their lives. Such colossal and misplaced hubris is a rare thing, or could this really be ignorance? Could Fellowes not know that the effectiveness of this play is tied directly to its language?

The problems of Fellowes' adaptation are compounded by director Carlo Carlei, who doesn't shape scenes. He doesn't know what to emphasize and what to toss off, and he doesn't probe the characters' emotions. Potentially grand cinematic moments, such as the duel between Mercutio and Tybalt, lie flat on the screen. Worst of all, Carlei has no idea what to do with Hailee Steinfeld, who is so lost in the role of Juliet that it's shocking. If these are the takes that got in, one can only imagine what's on the cutting-room floor.

Really, you have not lived - or died a thousand deaths in a movie theater - until you've seen Steinfeld in the balcony scene, rushing through her lines without affect, barely opening her mouth, as though reading them as fast as she can, and without comprehension. No wonder they cut the climax of the scene, Juliet's lines about her "bounty" being as "boundless as the sea" and her "love as deep." Steinfeld could never have played them. In fact, from the way she speaks the line "Wherefore art thou Romeo," it's actually possible that nobody told Steinfeld that "wherefore" means "why."

Here's the thing: Juliet is the great role in "Romeo and Juliet." It's her passion that propels the action, and if you don't have a Juliet, you're finished - even without the dead weight of Fellowes' ghastly, ruinous screenplay. And this is especially a shame because Douglas Booth as Romeo is quite good and could have been better, if only he had someone to play off of. It's almost pitiful to see him here, trying to inject emotion and wit into his scenes with Steinfeld, who is a blank wall. No wonder Booth's best moments are with Paul Giamatti as Friar Laurence, because there Booth gets to engage with an actor.

The idiocy literally begins three lines into the movie, when Fellowes introduces a jousting tournament that becomes the source of the current Montague-Capulet enmity. For this purpose, he turns the character of Mercutio into a Montague, when the whole point of the role is that he's neither, and yet gets caught up in the battles nonetheless. By the way, if the Prince of Verona wants peace between the two warring factions, why would he initiate a sports competition between the two? Is the point here that the prince is an idiot, or did no one think this through?

From there, it's more bad choices, more than can possibly be listed here. Here's one: When Juliet's cousin Tybalt and Mercutio duel, it's simply part of a larger scene of others dueling - like a Renaissance version of a bar fight. Another one: When Romeo goes into Verona, after his marriage to Juliet, he isn't surprised by Tybalt's hostility. No, he's warned in advance: "Tybalt has set forth in such a rage that there is trouble in the offing!"

Needless to say, Shakespeare didn't craft that pithy line, either. No, Shakespeare could write.