Well, that was on another plane from the usual KBL! The therapist finally showed emotion in the finale - great acting on his part. Even though they weren't actually performing, both men are incredibly fit! Don't know why I can't find anything about the 'therapist' - Kim Hyo-sub????
As one of the commenters on MDL said - I watched for JoongDunk. I must say, though, even Dunk was a bit disappointing - he was really stiff and wooden in this role - it didn't suit him. Joong was Joong - sexy and cute, with a bit of muscle thrown in . The plot was intriguing, but there was too much romancing going on with the MLs, who were supposed to be catching killers. The supporting cast - the college friends - were all good, and the doctor (played by Sing Harit) was excellent as the deranged character. The other deranged character - Fai - was played excellently by Pahn Pathita.
I adore JoongDunk, so I’m really just watching this for them. I’m on episode 8 and crawling through it at…
I agree with everything you said....I also only watched for JoongDunk, and even then, Dunk was a bit stilted. The BTS at the end showed his real character, and the director saying "You went right out of character"
Found it, thank you, but the subtitles stopped half way through the first part! Others noticed this....I will go back to it later, to see if it's fixed. Looks good so far, though....
K-Drama 
Joong - sexy and cute, with a bit of muscle thrown in . The plot was intriguing, but there was too much romancing going on with the MLs, who were supposed to be catching killers. The supporting
cast - the college friends - were all good, and the doctor (played by Sing Harit) was excellent as the deranged character. The other deranged character - Fai - was played excellently by Pahn Pathita.
What a nothing burger.