Just trying to get an idea of how to recreate this effect on a photo. Thanks for any advice.

This image looks like it may have been taken from two different sessions of images possibly.  The red and blue sets.  It looks like the images were "cut out" and then "re-composited" into this new version of the images with a new background added in possibly.  Or it also looks like maybe the colorization was added in later after the heads and bodies were composited.

Cutting out the images and compositing them into a new image is usually done by cutting out the original images from their  original backgrounds.  You can do this with several of Photoshop selection tools like the magic wand and quick selection tools.  These tools are sometimes OK if the backgrounds and edges are not too complex...otherwise they can produce less than precise cutout edges.  You can also use the quick mask function after this to touch up the edges (just hit Q) on your keyboard.  That will help fix some telltale bad edges.

For me,  I usually place the images on separate layers and then add a layer mask to each layer.  I then make selections use a cutting program like Vertus Fluid Mask or Topaz ( Cutting plugins costing approx $80+ USD).  But even with this i end up using the layer mask in the end of the process to make the best and cleanest cutouts... because by using a layer mask I can add and subtract from the edges manually and artistically by using just a black or white brush.  Once the background of the original image is removed and is transparent...then I would use the move or cut and paste tools to move the cut out person or face onto a new master layer or a new master image with a transparent background.  I would continue cutting out faces and bodies and dragging them onto the new composite image and arrange them till I was artistically happy with them.  I might add different visual touches to the images afterwards as well...such as making parts of them blue or red in this case possibly. 

This process is called usually "Compositing"...and you can find many YouTube tutorials on Masking, or Cutting, or Making Selections, or Compositing Images in Photoshop.  Fun stuff, but sometimes very challenging.  Best of Luck.

Edit after Post:  Wes, you have a gorgeous port... with a technically and artistically powerful command of photography.  The way you shoot with your backgrounds and lighting...you should be able to cut almost perfectly... and do amazing compositing work like the above with your images!  You seem to have retouched images as well.  Im surprised you havent  mastered compositing already.. given your other skills.  But... people are always at a different places. I guess I am too.