Partners in Crime - Episode 6 Review - N or M?

My review of last week's episode

Rules of the game: if a character is suspicious, you should look elsewhere for whodunit. Since last week found us pointing the finger at the quirky psychologist couple, the sprightly Mrs. Sprot (who Tommy likes), and the cunning Carl Denim (who Tuppence likes), it seemed a fairly safe bet that one of our other suspects would be the culprit.

(Spoilers.)

Partners in Crime - Episode 5 Review - N or M?

 My review of last week's episode

If Tommy and Tuppence Beresford are all that stand between England and an atomic blast, England had better start worrying. Last week left Tuppence facing down an angry Major Khan, whose room she had broken into. It only takes a few minutes and a gun for Tuppence to spill all: name, true identity, mission. Luckily, Major Khan is not N, and is confident enough that Tuppence is not N that he lets her go.

Lest we still suspect him, he's swiftly dispatched in a suspicious suicide at a party Tommy and Tuppence wheedled their way into attending. Meeting up with Carter and Albert, Tommy and Tuppence learn that matters are far more serious than they imagined, but for reasons unknown, Carter can still offer no concrete aid.