There's nothing 'missing' at all - the track does this several times; just your ear has got used to it by the 2nd or 3rd time. This one feels odd because it's the first one that really establishes the 'beat'.
The bar before ends with a string line descending through 3, 4, then there's a bass note [really a low-voiced chord] on beat 1, with a broader spread of the full chord following on the 2. The next 6 or 8 bars don't emphasise that push quite so much, but you hear it again a couple of times by the time she reaches the top of the hill.
This is just 4 bars from just before 0:30 to just after - a piano score so not exactly the same as the soundtrack - with the push circled.
I think if you want a more detailed explanation, then Music Practise & Theory would be a better place.