Plotting 2 dynamically-sized series on ONE line with Excel

here is my problem: with excel, plot 2 series on one line, where the first series has a changing size.
Here is an example to better understand it:

List_1: can be [0,1,2,3,4,0] or [0,1,2,...,15,16,0]

List_2: is always the same, eg: [0,1,2,3,0]

Time : I have a time column to use as an x-axis, eg: [0,0.1,0.2,...,2.50]

What I am looking for is a way to graph List_1 and List_2 on one continuous line in a graph.

I experimented with naming List_1 using the Name Manager in Excel, but I can’t seem to make out of 2 lists only one.
I also tries the CONCATENATE() function in Excel to no success, in fact what I need is an array, not an un-seperated string of numbers

Thank you very much !