Taylor Swift does it again! The Shake It Off singer showed up at the Sycamore Tavern in Hollywood on Saturday to perform for a couple’s engagement party — and she shocked EVERYONE when walking in the door! There’s a connection here: one half of the newly engaged couple, Alex Goldschmidt (the taller guy in the clip) was in the Shake It Off music video, and so when he reached out to Taylor about doing a sweet, simple acoustic number for the celebration, she was all about it! Ch-ch-check out the fun moment (above)! So cute!!!