Why it is beloved? It is a heist movie with a time travel twist. The Teller is the best monster introduced in Series 8. Why it's overrated? Clara and the Doctor wake up in a dark chamber with two other people: Psi, a hacker with an augmented brain, and Saibra, a mutant humanoid with the ability to shape shift. It's revealed that they agreed to wipe their own memories. A mysterious man known as "The Architect" briefs them on a mission to rob the impregnable Bank of Karabraxos. With no memory of why they agreed to rob a bank, the team reluctantly follow the Architect's instructions. The joy of watching a heist movie is that the audience get to see how the characters would think of a plan to sneak in to a seemingly impregnable place and have the satisfaction of seeing them put it to use. Time Heist doesn't have that luxury, though, given that the characters don't even have a plan. They are spoon fed by the architect who leaves them messages and useful tools at every checkpoint. The supporting cast don't fare any better, either. Psi and Saibra aren't as developed as they could be and Ms Delphox is a run-of-the-mill cartoon villain who is only identified by her occupation and spouts bad dialogue and exposition to boot. Credit where credit's due, though. The Teller is a terrifying monster who is able to telepathically kill anyone for basically just thinking. It's revealed in the end that the Architect is actually the Doctor. He arranged the memory erasing so that they could not be killed by the Teller. But if the Teller can kill them without any specific details of their plans, but off the back of random guilt alone, then what was the point? The Doctor was also the one who scattered the tools for the mission within the bank by using his TARDIS, so if the TARDIS can infiltrate the bank with no problem, a vehicle that can teleport through vaults, then why did the Doctor go through all the trouble to setting up the complex heist in the first place? It seems like the episode could've been over in a minute. Maybe that's why.