@wiggler, Based on your description, you want to perform Table Drilldown on a.project.owner field.
Following is a run anywhere example which created two a.project.owner values.
Table drilldown has following notable behavior:
1) Owner value is passed on to the second search only if a row in the a.project.owner field is selected. This is optional. As far as specific row with Owner Name you are interested in is clicked you can access the Owner value displayed in the table as explained in the next point.
2) a.project.owner value is access based on selected row using predefined table drilldown token $row.<fieldName>$
Depending on your Splunk version I think 6.5 and 6.6 drilldown options are available directly from the UI edit option. However, it is better if you familiarize yourself with Simple XML drilldown coding as well.