Complex sentence: Just the day before, DePalma arrived in Los Angeles and at around 4:35 PM, when he was crossing Wilshire Boulevard, he was hit by a bus and killed instantly (he was the man killed in the teaser).
Split into simpler sentences: Just the day before, DePalma arrived in Los Angeles. At around 4:35 PM, when he was crossing Wilshire Boulevard, he was hit by a bus and killed instantly (he was the man killed in the teaser).