Mrs Brown is concerned that her family are keeping too many secrets. Her daughter, Cathy, won't tell anyone about her new boyfriend and son Mark won't tell anyone why wife Betty has thrown him out. To add to Mrs Brown's worries, Maria's mother pays a disastrous visit to discuss the upcoming wedding between her daughter and Mrs Brown's younger son, Dermot.

When Betty and Mrs Brown meet to discuss the situation with Mark they unsurprisingly come to blows. Unfortunately, this all happens in front of Maria's well-to-do mother. Horrified by what she's seen, Maria's mother is determined that the Brown family shouldn't attend the wedding.

At the pub, Mrs Brown spots Betty with another man. Can it be that the secret is not Mark's, but Betty's? It's time for Mrs Brown to do what she does best, and meddle in her family's affairs.