In the Amazon Prime TV series “Homecoming”, creator Sam Esmail uses the look of the show as a character, just as he uses actors as characters.
**absolute spoilers ahead**
The show’s main timeline (set in present day) is displayed in 16:9 widescreen. The picture is clear, wide and the colors pop. Heidi, played by Julia Roberts, has just started a new career and her life looks promising, so we see the big picture. When the show goes into a future timeline, the ratio is restricted to 4:3, nearly a square. The scenes from the future feel claustrophobic, messy and the color is flat. Fans of the show understand that in the future scenes Heidi is missing memories from her past and she feels conflicted about “things” she may have done but can’t remember.
To give us viewers credit, we could (should) easily be able to follow along as the story jumps between timelines. We survived movies like “Memento” after all…However, something about the aspect ratio expanding and shrinking, really does evoke a physical reaction to the scenes. You almost release your breath as the aspect ratio jumps to 16:9 from the hard-to-breath 4:3, your eyes adjust and you easily connect with the timeline.
The big payoff Sam Esmail gives the audience, is a pivotal scene in the last episode, where the main character Heidi finally has a breakthrough and remembers something from her past (main timeline) while in the future. The two timelines collide and the frame is pushed with Heidi center screen and the aspect ratio widening from 4:3 to 16:19 in a seamless effect. Pretty epic to see/feel. 
The use of aspect ratio as a character is not something that I forsee being used often in TV and Film. But cheers to Homecoming for attempting something different! The creators of the show used every visual element they could to help tell the story…from long, uncut shots, to set builds to unique camera rigs. It is an absolute visual treat. Give it a watch if you haven’t already.