Dennis and Rachel proved the most determined housemates in the latest Big Brother challenge, but then wasted their reward because they thought it was part of a secret task.

After all the housemates were charged with carrying out a lightbulb task – holding onto a switch above their head to make sure a red light didn’t come on – most fell by the wayside pretty quickly.

But the Scottish dance student and Welsh trainee teacher proved they had the willpower, lasting one hour and 55 minutes, and were named joint winners by Big Brother.

The pair headed for the Diary Room, where Dennis told Big Brother they ‘felt fabulous’, if a bit sore.

They were rewarded with a picnic for two in the garden – which they were not allowed to share with the other housemates.

But the paranoid pair then spent several minutes staring at the food, debating about whether the picnic was in fact a task and if they were allowed to start eating.

“This is terrible isn’t it?” said a stressed-out Rachel.

In the end they let the delicious food go to waste, fearing that it may impact on their shopping budget.

And they were left looking foolish when they returned to the Diary Room to be told by Big Brother that they had just missed out on what was simply a treat for passing the task.

How to turn victory into failure!