While Clara is prepping for a date with Danny, The Doctor is trying to convince her to join him for another adventure aboard the TARDIS. A flashback shows Danny setting a time with her for the date, and that its been two months for them. As she's about to leave her flat (apartment) the phone rings on the TARDIS, parked in her spare room, when he answers the phone Clara and The Doctor are both suddenly sitting at a table with two others, all of them holding memory worms, last seen in The Snowmen, christmas special.
A quick briefing tells them that they've agreed to rob the Bank of Karabraxos, the most secured and fortified bank in the Universe. Their presence has set off alarms and a living guilt detector is issued to find them, The Teller. Nice double-entendre. The bank finds that they didn't get the right intruder, and continues their search. Meanwhile The Doctor and crew continue to make their way to the valts.
The question of the Good Man, came up again. As Saibra face agonizing death, she said, "Oh! A good man. I left it late to meet one of those." then she takes the exit strategy. Once Psi does his job of unlocking the 24 keys of the vault, he is sacrificed.
The Doctor and Clara are left to retrieving the things they want from the vaults, only to get caught themselves. As they think they're getting incinerated by a couple of guards, they discover the guards are Psi and Saibra in disguise and the exit strategy wasn't a vapourized body, but a teleport.
Off they go to finish the job and reunite The Teller with his mate, and at the end Clara with her date.
The episode really is a paradox, Madame Karabraxos calls the Doctor because he gave her his number in the past, but if she hadn't called and set-up the heist, he wouldn't have met her in the past and been able to give her his number,
Next time on Doctor Who: The Caretaker
Welcome to Coal Hill, Mr. Smith