It takes a long time for this Mario / Luigi team-up to become enjoyable. After a procession of wordy tutorials dominates the first few hours, the core gameplay finally emerges. And what springs forth is a surprisingly involving RPG adventure.

You take control of the titular duo across Pi’illo Island, a holiday retreat for Princess Peach and friends. Much of the time is spent controlling both characters simultaneously around a series of 3D and 2.5D environments, battling monsters and solving puzzles. The breadth of gameplay is impressive, and the duality of the central pairing is often used in interesting ways. But it can be a real slog having to control both characters at once, especially when navigating platform sections.

While the backgrounds lack scale and it generally fails to impress visually, the jaunty soundtrack and quirky set of characters ensures the journey is an entertaining one. Unlike most 3DS titles, this is a deep and complex slow-burning adventure, best picked up when you have plenty of time on your hands.