Alan and Walden must be perceived as a loving couple during a meeting with an adoption social worker. However, Lyndsey returns from rehab and makes their plans more difficult.
Walden hopes to create the perfect Christmas experience for Louis, who has lost his faith in Christmas. But Santa, Alan's mom Evelyn, and Alan's cheapness threaten to ruin everything.
Walden and Laurel set up a playdate for their kids so they can pick up where they left off the last time they got together. Meanwhile, Herb asks Alan if he can ask Lyndsey out.
When Ms. McMartin discovers that Walden and Alan are pretending to be gay, she threatens to take Louis away. However, Alan has a plan to help her change her mind.
Walden discovers that Ms. McMartin is crazy and needy after they hook up, but he doesn't want to break up with her and mess up the adoption. Meanwhile, Lyndsey asks Alan to move in with her.