As long as you're in the FULL recovery model, this should be simple.

1) set the file to be offline using ALTER DATABASE dbname MODIFY FILE

2) restore the initial image of the file from your last full backup, specifying the name of the file you want to restore:

RESTORE DATABASE dbname FILE = 'full pathname and filename of the file'

FROM DISK = .... and so on

3) restore all log backups you currently have since the last full backup, using WITH NORECOVERY. Only log records pertaining to that file will be restored.

4) take a backup of the 'tail of the log' using

BACKUP LOG dbname TO DISK = .... WITH NO_TRUNCATE

5) restore the 'tail of the log' backup using WITH NORECOVERY

6) complete the operation using RESTORE DATABASE dbname WITH RECOVERY

This brings the file right up to the same point in time as the rest of the database.

Let me know how you get on.