Legion Chapter 21
In this episode, we see the anger of David when sid rejects him. David has love for sid but sid is well intent on killing David. it is clear that sid has no intention of sparing Davids life. Sid is still angry at David and her once love for him has been converted to hate. Davids reaction is to get angry and this is shown as red colour and clouds and lightning above him. The drugs throughout his compound are no longer blue and now red so instead of giving love and peace to people, the drugs make people violent.
The shadow king says he will teach sid to lie. Shown in the quote “Intimacy we need is emotional not physical I will teach you to lie so well David thanks you when you stab him in the back”. So in the future, I think what they talked about implies that sid will pretend to be on Davids side and they betray him and kill him.
We find out that David cannot travel through the time doorway in order to enter the time hallway to travel through time. So to solve this Lenny kidnaps Male Cary and David makes Cary help switch to amplify her powers. Presumably, so David can travel through time aswell.