Like the long-haired teen heartthrobs before him, Shawn Mendes has covered “Can’t Take My Eyes Off You.†But unlike Patrick Verona in 10 Things I Hate About You, Mendes has no girl to get, so his Frankie Valli cover is just a reminder that, yes, he and Camila Cabello are hopelessly in love. He goes to great lengths to remind us of that fact in the BBC Radio 1 Live Lounge, where he also performed current single “Wonder.†What starts as a standard-fare piano-ballad performance turns into an over-the-top art-pop mess (not like that) when Mendes brings in an explosive wall of cymbals, synthesizers, and guitars. Sounds like someone’s been listening to the new Perfume Genius album in quarantine? By that finale key change, it’s all entirely too much to be true. At least he’s keeping us wondering what other shenanigans he has in store ahead of the album release on December 4.