Database

db={people:[{_id:ObjectId("5e12f6260c190f8ee91b162d"),name:"Joe Bookreader",address:"Highway To Hell 21"}],addresses:[{street:"123 Fake Street",city:"Faketon",state:"MA",zip:"12345"}]}

Query

db.people.aggregate([{$lookup:{from:"addresses",pipeline:[],as:"address"}}])

Result