It will be a long time before Buffy’s season six musical “Once More, With Feeling” will be dethroned. With wholly original music, fair use of its entire cast (even the ones who couldn’t sing), and season defining functions which included a game-changing revelation, The Flash’s “Duet” is a far cry from the bar that has been set. Nevertheless, it’s a great episode. Recent events in both The Flash and Supergirl have been somewhat less than logical, and almost teetering on Arrow season 4 standards (read: wtf break-ups?!). Thankfully, those little plot deviations turned out to be a set-up for this. While the episode’s writing didn’t feel as smooth as it could have been, a brilliant touch of the script was to explain it away as the general story-telling tone of musicals. And, of course, the inclusion of fan favourites from across the CW DCTVU, including Flash alum and current Legends of Tomorrow cast member Victor Garber and his fellow Legend / Arrow mainstay John Barrowman, is just the icing on the cake… Making Grant Gustin’s ex-Glee co-star Darren Criss, the cherry on top. Assuming the role of the Music Meister (a character created for the Batman: Brave and the Bold animated series, and portrayed by yet another ex-Glee actor, Neil Patrick Harris) Criss functions as the mysterious and possibly mystical antagonist whose presence seem to be warranted purely to… well, fix plot points that no one would have wanted to dedicate any other episode to. Yeah, so that was a pretty big weak point of the episode—a very conveniently placed event that just helped to wrap things up in time for the race towards the finales. On another note, the episode features two original songs, “Runnin’ Home to You” by La La Land’s “City of Stars” lyricists , Benji Pasek and Justin Paul, and “Super Friend” by Rachel Bloom and Tom Root of Robot Chicken fame. My definite favourite of the two would have to be “Super Friends” thanks to Bloom’s and Root’s great sense of humour, and ’cause the reprisal of “Runnin’ Home to You” was, well, just odd. While the episode was certainly a fun break for The Flash, the show needs to get back on track with its Savitar issue, and bring the Iris problem to a closure soon.