When a penniless young writer steals a suitcase full of “dirty money” a Yakuza enforcer is sent to track him down. The writer would rather kill himself than be captured but the enforcer is under oath to kill himself if he fails.

Just to clarify it is SEPPUKU http://en.wikipedia.org/wiki/Seppuku
Only mentioning the correct terminology because it is a vital component.

OK -- just a few questions:

Does he kill himself?

If not, does he tell anyone of his plan to kill himself if he's caught?

If so, who does he tell and when (1st, 2nd, or 3rd Act , climax etc..)?

Lastly -- 'a last ditch effort to save himself from torture AND to avoid placing the people he gave the money to in danger...' -- Being prepared to kill himself to save anyone, let alone (I'm assuming) the large number of people at the charity, is a huge thing to do -- doing it to also save himself from torture feels like a bit of a contradiction... it has much more power (and he has much more power) if he is doing it only for the innocent charity people. It actually has the potential for a killer (minding the pun) ending -- but I might be a tad biased as it's something I'm considering for the end of what I'm working on... ;) I guess it could work if he reveals his plan on topping himself when caught to avoid torture near the start, but at the end it's just 'for the kids...'... still...

I know loglines can send you insane (they certainly do me...) and I hope you don't feel I've been too harsh. I still like the idea of a protag and antag both being bound to a SEPUKKU... but obviously it's not this movie.

Good luck.

Going for something straightforward that might not have the same appeal as previous attempts:

When a penniless young writer steals a suitcase full of 'dirty money' a Yakuza enforcer is sent to track him down and an epic battle begins on the streets of East London.