Season 5 concludes with opportunities abounding for everyone at the agency, while Pete encounters an interesting stranger on a train.

Don receives an intriguing lead and follows up on it.

Don deals with a challenging pitch, while Peggy ponders taking a trip.

Christmas proves rewarding to many at the agency; Harry does a good turn for a friend.

Don's competitive nature comes to the fore; Roger pursues some new clients; Sally is met with a challenge.

Peggy reluctantly harbors a secret; Pete steps up for a friend; Don gets a surprise.

Don, Roger and Pete team up to rustle up some new clients; Sally lends a hand to a relative.

Peggy has a tough time during a particularly formidable pitch; Don calls on a potential client.

Lane makes an interesting friend; Pete plays host to an assortment of guests.

Don has an encounter with someone from the past; Joan comes to a momentous decision. Meanwhile, Roger increases Peggy's workload.

Peggy receives new responsibilities as the firm makes a concentrated push to increase business. Later, Don and Harry go the extra mile for a big client.

Don is greeted with a surprise; Roger and Pete clash; and Joan has a run-in with a houseguest.

Don is greeted with a surprise; Roger and Pete clash; and Joan has a run-in with a houseguest.