The only one I have noticed so far is Flash(Gordon).

I haven't opened the package but there is no mention of a blu-ray version on the cover or back just the special features on blu-ray.

It seems to have happened several times with the Best Buy 4K steelbooks. I know I had basically given away my (Burton series) Batman blu-rays when I found out the set didn't have them (and all the special features) in the package.

Last year’s Shaft movie was a Best Buy exclusive on 4K and did not include a regular Blu-ray. There’s also a Michael Schenker concert disc that is 4K only, and the past few DTS demo discs given out at CES.

The recent Blue Underground UHD of Fulci’s House by the Cemetery does not have a BD of the film. It does include a BD of special features, but it does not have the film. Curiously enough the other BU UHDs of Fulci’s films do seem to include the film on BD, just not HBTC.

Days of Thunder doesn't have a blu-ray version included. I wasn't paying attention when I bought it. I haven't upgraded to a 4K tv yet, but I wanted to future-proof my purchase. At least I can watch the digital copy.

Of Blue Underground's "catch-up" titles -- the ones that'd recently gotten a 3-disc Blu-ray limited edition release -- only The New York Ripper was a UHD + BD combo pack. Everything else was UHD BD + a BD of extras. (And Ripper was likely only an exception because its 3-disc release was BD+DVD+CD, while the others were BD+extras BD+CD.)

But they've moved to single SKU combos, starting with Daughters of Darkness, so that shouldn't be an issue going forward with them.

Synapse's Suspiria release is another one that's not a combo. Discotek’s Space Adventure Cobra as well.

Well fuck that purchase then. I was going to give my son the blu.

If you have a 4K player, you can still watch it on a non-4K television, it just won't be in 4K. My 4K player (had to get a new player as this one stopped loading newer Blu-rays for some reason) is connected to my old 720p TV from like 15+ years ago, and plays fine just with a message about needing to connect to a 4K TV to view in 4K.

Anyway, add Arrow's new Tremors to the list of 4K only.

Is Tremors UHD a limited print run or something? Going for $90 or so on eBay

Saw that as well. It is a Limited Edition with I assume a standard release (without all the frills and second disc) coming out down the line. Seen this before with other Arrow releases.