Explanation

Wow, what a terrible movie! Not a single reviewer could think of one nice thing to say? You need two words that mean something like “unanimously criticized” or “100% disliked.”

Roundly means “emphatically,” or “so thoroughly as to leave no doubt.” Panned means “reviewed negatively” and is almost always used to refer to plays, movies, etc., so the word is a perfect match here.

Roundly, panned.
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