First of all, "Obrigado a Matar" translates to "Forced to Kill", as in "I have no other option but to commit a murder". The word "obrigado" means both "forced to" and "thank you" in Portuguese, so don't get that mixed up!
Now for the movie...
It's really hard to understand what was going on during the production of this. One thing for sure is that nobody knew exactly what they were doing. The best way to describe it is to compare it with any home made short movies that kids would do for school, but with adults.
This 40 minutes "masterpiece" is extremely obscure by movie standards, but its opening scene became widely popular in Brazil due to its amazingly bad acting and special effects. How did it made its way to the internet I have no idea, because it was probably released for a very small public in the town of Lages, a rural area of Brazil. Whatever the case, though, everybody should watch at least its opening scene once, even if you can't understand the (hilariously poor written) dialogue.
I mean, it's amazing. How someone could possibly gather so many ordinary people to act as if they were in a real movie goes beyond any explanation I could give. It's fascinating how nobody starts laughing during this whole thing, everybody just acts as if this is the real deal. The passage of time in this movie also makes absolutely no sense; If I understood it right (which frankly no one can really tell), in a matter of 3 months João Amorim's daughter grew, like, 10 years or so! Or maybe he has two daughters, but the movie makes it as clear as the bottom of the ocean. And even worst, both Amorim and his daughter apparently suffer from a severe case of amnesia during a very critical moment of the movie. How the hell couldn't they remember something that should have marked their lives forever?! It gets really awful!
I don't want to get into spoilers here, but man that ending is something. Oh, and it's a musical too! Every time Amorim starts singing it is the most obvious dub you could possibly imagine, but it fills me with delight. It's a shame this movie may not be as funny to people from other countries as it is for Brazilians, but I just love it. It's the most awful thing I'll ever see in my life! And don't even try to tell me that another movie is the best at being the worst without watching at least this movie's opening.
The Room got nothing on this golden turd.