I admit it - I don't generally like movies where there are no appealing characters. And that being the case here, my review is suspect.
"Frank" starts with Jon (Domhnall Gleeson), a passable musician but aspiring and horrible songwriter, who finds himself taken on as the keyboard player for the Soronprfbs (sic), a band led by Frank (Michael Fassbender). Frank is the leader of the band, and he wears a papier-mâché head - all the time (including sleeping and in the shower, where he bags it). Jon then joins them to record their new album, an epic undertaking full of broken personalities. Jon's postings on Twitter and YouTube net them something resembling an audience, and a trip to SXSW, where everything comes to a head.
You can make a movie - many have - with a bunch of unpleasant people doing obnoxious or unpleasant things. And that's pretty much how I see this movie. I really didn't like it ... but the person who watched it with me loved it. And so did the critics.