Gnuplot: Joining points between two sequences using lines

Question

Hi All,

I have two sequences in two files with each row representing a point in 3D/2D like

1 1 1
2 3 4
5 2 3

and

2 3 3
2 2 1
4 2 1

I want to plot these two sequences in one graph which is pretty easy. But what else I want to do is draw a line from 1st point of 1st sequence to 1st point of 2nd sequence continuing same for all other points in that graph. Also it would be helpful if I could draw lines for alternative points i.e first plot a line joining first points of both sequence and then directly plot another line joining 3rd points from both sequences without joining the second points. Is it possible to do so?

Thanks,

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