In the United States, Donald J. Trump and Joe Biden can barely agree to share a stage for a debate.

In Belgium, the politicians who will face off on Sunday in the country’s most contested general election in years agreed to a four-episode reality show filmed over a weekend and set in a castle — moat and all.

The show, a political version of “The Bachelor” called “The Conclave,” transfixed Belgians in the run-up to the vote for the country’s national and regional parliaments. The elections are coinciding with those for a European Parliament this weekend, in which 27 European Union countries will vote.

As in many other European countries, the mainstream political establishment in Belgium has shrunk electorally. The far right has surged.

But for Belgium, that dynamic is further complicated by the divide between the country’s French-speaking south, Wallonia, and its Dutch-speaking north, Flanders.

The show’s conceit is centered on the personal dynamics among politicians who are rivals but must ultimately work together to manage the rise of the far right. Perhaps by putting them together for a few days, they can resolve some of their differences.

If nothing else, the show succeeded in airing the grievances that have made a far-right, anti-immigrant, Flemish secessionist party, Vlaams Belang, the election front-runner. A victory for the party could precipitate a crisis for Belgium by thrusting the issue of Flemish independence to the top of the political agenda and threatening to break the country in two.