The Ben Tiller Band
The name is a play on real 1940s bandleader Glenn Miller. Jem and the Holograms accidentally get sent back in time by Techrat's time machine to London, 1944. They run into Ben Tiller, and sing "We're Making It Happen" with his band. Then a Nazi bomb explodes outside the club. Fortunately, they're yanked away in time to Woodstock in 1969 where they run into Johnny Beldrix.