altid-lookup.js

var query = {$or: [
  {_id: req.params.id, app: req.app.id},
  {altId: req.params.id, app: req.app.id}
]}
 
Show.findOne(query, function(err, show) {
  // send them the show
})

the-data.js

{
  _id: ObjectId('5124f5bcd214260200000117'),
  altId: '18',
  title: 'Compulsive Love',
  ...
}