NSInteger is a scalar and not an object. So you shouldn’t retain it, it should be assigned. Changing your property will clear up the warning message. You don’t need to do the NSNumber stuff that you added in.
@property (nonatomic, assign) NSInteger movieId;
It’s a little confusing since NSInteger sounds like a class, but it’s just a typedef for int. Apple introduced it as part of 64-bit support so that they can typedef it to the appropriately sized integer for the processor the code is being compiled for.