Filming of this movie took only eighteen days.

Included on the DVD's 'Special Features', is the film of the actual police crime scene investigation, which was recorded on July 1st, 1981.

On July 1st, 2003, the anniversary of the murders, Josh Lucas and Val Kilmer spent an entire night in the actual Wonderland house.

Cast and crew were evacuated on the last day of the shoot due to a fire.

In reality John didn't call Eddie Nash after the robbery at his place, but instead he was seen in Hollywood by Nash's associates, who saw him wearing some of the jewelry which was stolen in the robbery. They told Nash, and John was soon taken by two armed men who brought him to Nash...

The shots seen during murder scene, from John Holmes' perspective, are the real LAPD crime scene photos of the actual corpses.

Val Kilmer became so engrossed in the film's production, that he created a 'behind-the-scenes pictorial book', which he has not released publicly.

Christina Applegate, who grew up near the site of the infamous Wonderland murders, remembers seeing the bloody mattresses lying on the street. Because of this, she agreed to take on the small role of Susan Launius.