Smile Time - S5-E14
Corrected entry: When Fred, Wesley, Gunn and Angel plan to go to the studio where "Smile Time" is filmed and they are about to leave, Puppet Angel takes a sword down from the wall behind his desk. Fred opens the door and Puppet Angel is still behind his desk. However, as they walk down the hall when the dramatic music begins to play, Puppet Angel is suddenly in front of the group. There wasn't enough time for Angel to get in front of them when Fred opens the door.
Correction: When they leave the office it is a new scene, there's no indication of how much time has passed so it's perfectly plausible that Angel is now in front.