Like many other people noticed already, this movie is a commercial for Korea. And seeing how it's like that, many things that normally don't make sense somehow do make sense!
The basic story is about a photographer who meets a screenwriter. The screenwriter is actually together with an Actor, on the way to meeting him. Sadly, she's having a writers block, so all her scenarios are rather bad. As she tries to find inspiration, the photographer helps her find it. And while she's doing that, you can see Big Bang driving around and making a surprise for school kids.
Seeing that they wanted to advertise Korea, they inserted a loooot of beautiful landscape, lots of brands and city-shots, food and their music - with Big Bang. The scenes with Big Bang really felt wrong, but since it's an ad, they tried to insert the biggest group of Korea into this movie. It was fine, just that it felt awkward when they were driving around through Korea and in the back you could hear Super Junior sing the soundtrack for the mvoie...
All in all, the dialogues were bad and the story boring. But a fan of Korea would probably still be able to enjoy every second of it. I'm not saying it was bad, just that it could've been made better. They gave their all into the cast and the scenery, cuts and music. Just the story is lacking, so I was a bit disappointed that they couldn't put more effort in that part, when everyting else was good.
3* from me and if you like Korea, you can watch this beautiful 30 minutes advertisment for the korean culture!