Complex sentence: In "Pizza Face", she insisted April to watch a scary movie with her, but April lies to her that she has a date with Casey, though Irma is suspicious and wandering about her four friends that she won't let her see.
Split into simpler sentences: In "Pizza Face", she insisted April to watch a scary movie with her, but April lies to her that she has a date with Casey, though Irma doesn't believe the "dating with Casey" excuse. She is also suspicious and wandering about her "four secret friends" that she won't let her see.