Complex sentence: She hides under his bed and unbeknownst to her, her hair clip falls out, which Maxxie notices the following morning realising it probably belongs to his stalker, which he later discovers to be Sketch when he notices her wearing an identical clip and carrying a camera.
Split into simpler sentences: She hides under his bed and unbeknownst to her, her hair clip falls out, which Maxxie later finds. The next day Maxxie realises that Sketch is his stalker when he notices her wearing an identical clip and carrying a camera.