These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Rachel McAdams appears as Riley's bulimic sister in a season 3 episode.
Shawn Ashmore plays a guy Kayla goes out with named Chet in Jett's "Groundhog Day" Loop. His twin brother Aaron appears as an unrelated character.
Ashmore's Animorphs co-star Brooke Nevin was in an episode as well.
Trailers Always Lie: It was common for advertisements to only showcase the "Silverstone" part of the show, making the show look like a spy series. One can only imagine the reactions of people who were fooled by this, and then saw the actual show.