Peep Show follows the sexually-frustrated lives of two men in their late twenties, Mark and Jeremy. Having met while at the fictional Dartmouth University together, they refer to themselves as 'The El Dude Brothers' in reference to their student days. They now share a flat in Croydon, South London.

Mark is a loan manager and the more financially successful of the two, but is extremely uncomfortable socially and pessimistic about everything. Jeremy now rents Mark's spare room. He usually has a much more optimistic and energetic outlook on the world than Mark, yet his talent as a musician is yet to be recognised, and he is not as socially popular or sexually attractive as he would like to think he is.