If you loved Dragon Ball: Sleeping Princess in Devil's Castle, try Dragon Ball Z: Dead Zone
A bridge between a film you've already seen and one most people haven't. Here's what they share, and what the second one does that the first one doesn't.
You already loved

Dragon Ball: Sleeping Princess in Devil's Castle
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Dragon Ball Z: Dead Zone
What they share
Both films are directed by Daisuke Nishio, and they sit in Action / Animation / Fantasy territory. If that's the register that drew you to Dragon Ball: Sleeping Princess in Devil's Castle, the second film will land in a comparable space — through a different lens.
What Dragon Ball Z: Dead Zone is
You train in solitude, always pushing toward new levels of strength. But a foe appears, seeking the Dragon Balls to gain immortality. He kidnaps your son. Director Daisuke Nishio's first film is a concentrated dose of the series' action. The film leaves one wondering if Goku can ever know true peace.