Contains spoilers for Supergirl Season 4, Episode 16.
Lex Luthor's long-awaited introduction on Supergirl has switched up the show's dynamic rather late in the game but, after what we saw last week, that is by no means a bad thing. Assisting his sister in the manufacturing of her Harun-El drug, he turned on her after he obtained what he needed and set off as a free man. A deliciously evil heel turn for the criminal mastermind, Jon Cryer played his role to perfection and, quite frankly, breathed some much-needed life into the show.
Lex's crusade against Kryptonians continued in 'The House Of L' as the show flashed back a few months to reveal that he was familiar with Supergirl's seemingly evil doppelganger a.k.a. the Red Daughter. It was here that viewers learned he was actually a lot more integral to this season's plot than anyone ever thought as he attempted to bend her to his own will.
'The House Of L' was a well-structured flashback piece that managed to work its way round the entire season, filling in the blanks to add some much-needed context to the Red Daughter's story. In doing so, it has unmasked a far more interesting storyline.