We're off to see the lizard! Johnny Depp's heroic chameleon led 'Rango' to a No. 1 debut at the box office this weekend with an estimated $38.0 million.

The cartoon Western with the all-animal cast had been expected to open a bit higher, in the $40-44 million range. It may have been hurt by the fact that it wasn't in 3D (it's the first animated feature in recent memory that isn't), by competition from the still-strong 'Gnomeo & Juliet' and by middling word-of-mouth (kids may have enjoyed it more if so many of the jokes weren't pitched over their heads). Still, positive reviews, a broad release pattern (nearly 4,000 screens), ubiquitous marketing and the beloved Depp helped give 'Rango' the biggest per-screen average ($9,701 per venue) of any wide-release film this weekend.

Opening in second place, Matt Damon's 'The Adjustment Bureau' did a a couple million better than expected, bringing in an estimated $20.9 million. The figure is especially impressive given that 'Bureau' was targeted at the same adult drama audience already being served by such films as 'Unknown,' 'The King's Speech,' and Damon's own 'True Grit.' The sci-fi romance benefited from evocative marketing that made it look a lot like last year's smash 'Inception.' The movie marks Matt Damon's best opening since 'The Bourne Ultimatum' four years ago.