Site Hacked????

I have recently been working on a site for my friend and until yesterday i have had no issues.

When I went to view the site yesterday I found that when the homepage loads I am requested to fill out a survey before I can look at the site.

Does anybody have any ideas as to why this would be happening? I have tried with another theme and I do not have the same result, this on;y happens when I use the current theme

Hope you guys can help 🙂

Cheers