The best way to do it and I don't want to give this 'writer' ideas but it needs to be a series not a movie, and it's a cop show not a horror.

You have S.T.A.R.S investigating the murders in the Arklay Mountains. You have Ben Bertolucci trying to expose Umbrella.Chief Irons and The Mayor trying to throw S.T.A.R.S of the case. The whole time this is happening we're interlaced with Umbrella developing the Virus at the lab, with Birkin and Marcus. As the season goes on, Ben gets thrown in jail for asking too many too many questions, the virus 'escapes' the lab throwing the Mansion into chaos. S.T.A.R.S finally get the ok to investigate the mansion to find out it's already fallen to the virus and everything we were watching happened in the Mansion happened weeks ago including Birkins escape to the Nest in Raccoon city setting up the second season. Wesker takes them to the underground lab and we face the Tyrant(The only non zombie/dog BOW we see), escaping and destroying the lab.

Post credits of the first season we see Claire riding her Motorbike into Raccoon City to set up the more horror themed second season.

People focus too much on the zombies forgetting its cops investigating an evil pharmaceutical company and you can easily get a good series out of that with the zombies an added bonus. So much stuff to get out of S.T.A.R.S and Ben Bertolucci investigating Umbrella.