Out of the group, Harry only knew Lupin from before, and had spoken to the real Alastor Moody and Dedalus Diggle only briefly. This was Harry's first meeting with the remaining members, most notably Nymphadora Tonks and Kingsley Shacklebolt.[1]
The Advance Guard en route to the headquarters of the Order of the Phoenix
The Advance Guard and Harry travelled to Grimmauld Place by Broomstick, flying in formation with Tonks flying in front of Harry, Lupin underneath, Moody behind and the rest circling. There was a rear guard set up, so that if anything happened to the advance guard, the rear guard could take over, but this was, fortunately, not required.[1]
Alastor Moody suggested the entire group travel above cloud level for better concealment, but he was overruled by Nymphadora Tonks, who protested they would get soaked with water. Later, he also suggested that they double back to ensure that they were not being followed, but Tonks once again screamed at him, and the group was saved by their arrival at Grimmauld Place.[1]
In the film adaptation of Harry Potter and the Order of the Phoenix, Remus Lupin, Dedalus Diggle, Hestia Jones and Sturgis Podmore were not a part of the Advance Guard, and the latter two did not appear in the film at all. The only person other than Lupin that Harry recognised was Moody, but given that Harry only met Barty Crouch Jnr impersonating Moody, he would not be someone Harry would have trusted. Harry also calls him "Professor Moody" even though it wasn't actually him the previous year.
Hestia Jones and Sturgis Podmore are the only members of the Advance Guard to not appear in any of the films. Podmore is the only one who appears in neither the films nor the video games.
In an early script for the film adaptation of Harry Potter and the Order of the Phoenix, the Advance Guard are besieged by a pair of Dementors (possibly the same ones that attacked Harry and Dudley earlier that night) en route to Grimmauld Place. Moody and Tonks would have escorted Harry safely to Grimmauld Place, with the rest of the guard arriving shortly after once the Dementors were driven off. The same script also consistently and incorrectly refers to them as the "advanced guard".[2]