Krys Marshall

Marshall bequeaths a "slap bet" slap to Ted and Robin; Lily's estranged father (Chris Elliott) visits for Thanksgiving.

The BAU tracks a serial killer who chooses junkies, prostitutes and the homeless off the streets of Detroit as his victims.

Hours after calling Gibbs about a possible case, a Marine is found dead in Quantico; McGee and Bishop pose as a married couple.

Kara steps in to help Lena when she is threatened by Morgan; Alex wants to run tests to help Sam.

J'onn, Winn and Mon-El band together to fix the Legion ship.

As Kevin stresses about the premiere of his play, he receives support from an unexpected source. Randall struggles under the pressure of both his work and ailing father. Rebecca and Jack's Valentine's Day doesn't go as planned.