The "Supergirl" episode "In Search of Lost Time" directed by Andi Armaganian, airs April 23, 2018 on The CW:
"...when 'Myr'nn' (Carl Lumbly) inadvertently causes psychic disturbances at the 'DEO', 'Supergirl' (Melissa Benoist) must work with 'J'onn' (David Harewood) to contain the resulting chaos.
"Meanwhile, 'Mon-El' (Chris Wood) begins training 'Kara' in fighting techniques he's learned in the future for battling 'Worldkillers'..."
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