How to drill on datetime data without aggregating into level above

I have some data with a DateTime column. What I need to be able to do is drill down to the second level. I've created my own hierarchy Year>month>day>hours>minutes>seconds.

The only problem is if I plot some data on a line chart, and I drill down to the day, hours, minutes or seconds level, the data is grouped by the whole amount.

For example, if I drill down to the Day7 level, it will give me the data for all Day7's across all months. Or if I drill down to hour4, it will aggregate across every hour4, across every day of every month of every year.

so this sample data has 2 days worth of data.

Below shows across 2 days:

If I drill down a level, it gives me the hours:

But as you can see the hours have been aggregated across both days. 

I wanted to see the trend across the 2 days, so expect the chart to look something like the following:

Apologies for the crude illustration, but how can something like this be achieved?