I'd say someone of approximately grade 3ish could manage it. It's just the ledger lines (in both clefs) and changing from bass to treble clef in the left hand which make it more complicated. It is a slow piece though.
The rest of the book varies in standard though but it has some great pieces in from films like Indiana Jones, Lion King, Beauty and The Beast, Forrest Gump, Star Trek, Ghost, Breakfast at Tiffanys, etc... It's a big book