Pennsylvania-based 84 Lumber's 90 second Super Bowl spot follows a mother and her daughter who leave their native Mexico to find a better life in the United States.
The commercial that aired during the big game cuts off before they get to the border, leaving viewers hanging.
Viewers were directed to the company website to complete the journey with a note that warns it contains content deemed too controversial for TV.
They say Fox called it too political and edited the TV spot to omit the final scene, which shows the pair blocked by a border wall.
In despair, they come across two doors.
The ad's tagline: "The will to succeed is always welcome here."
The company says their website crashed after a rush of people logged on to view this cliffhanger ending.
84 Lumber says their "aim was to tell an authentic story and not to engage in a marketing stunt."
84 Lumber's viral Super Bowl ad crashes website