Blooper

When Herschel and Sarah are getting married, Sarah is on the right when the photo is taken. When Ben shows Herschel the photo album, Sarah is on the left.

Ben says he has a criminal record, but he was just arrested that morning and made bail, he won't have a record until he convicted at his court date, if he is even convicted at all.

When Ben is standing in front of a television in his apartment speaking to Herschel, there is no reflection of Herschel, only Ben.

Herschel and Sarah fantasise about being so rich they can discover what it's like to experience the bubbles of seltzer water; however as the poor, European peasants they're established to be they would certainly know what bubbly liquid is like to drink, it being an integral part of the process needed to create small beer and any sort of fermented food, such as sauerkraut. All these things were staples of the European diet at the time.

When the doctor tells Herschel they've tracked down a relative, he tells him "He lives right here in Brooklyn", implying the hospital is in that borough. When Herschel and Ben get into the cab outside the hospital, Ben tells the driver that they are "going to Brooklyn", when it's established they're already there.

In the later scenes where Herschel switches identities with Ben; Ben is unable to prove his identity. However, both of the characters were processed and booked for assault earlier in the film; meaning both of their fingerprints would be on file. USCIS and ICE frequently use bio-metrics, including fingerprints, before physically deporting an alien.

Both Herschel and Ben go back to America in the last scene when Ben was just deported.