This movie catches a lot of flak, but this is usually based on the horrible looking and covered / clothed version of the film that played US television and has also been issued to death on VHS and DVD buy companies like Alpha, Unicorn, etc. This movie never had a theatrical release in the states, although it was picked up by Avco Embassy in 1973. In Spain at the time, when there was nudity involved, the filmmakers shot two versions, one with clothes and one with out. The fully uncut English dubbed export print was titled WEREWOLF NEVER SLEEPS and seems to have been released to home video only in Sweden back in the 80's. It can be found on Ebay and the likes and comes highly recommended. My guess is Avco cut the film down for a R rated release that never happened. In 1974 it was released by Avco to television titled FURY OF THE WOLFMAN and the clothed version was used for this TV print. Cut to 12 years later and FURY OF THE WOLFMAN pops up on home video on the Charter label. This version appears to be what Avco was going to release back in '73. It's the uncovered version, with some nudity that would never pass on TV or in a PG movie. There are several scenes on the Charter tape that play out with nudity that are clothed in the TV print ( the source for all those dollar Dud's and VHS editions ). But a comparison to the fully uncut WOLFMAN NEVER SLEEPS reveals that 2 scenes are cut on this version! ( spoilers in next paragraph ) The scene where Ilona has Waldermar chained to the wall and whips him after he transforms into the werewolf is incomplete. After whipping him into submission, she starts to remove her clothes and begins making love to the werewolf!!! The werewolf responds positively to these sexual shenanigans too. This scene certainly ranks as one of the most unusual in the history of horror films and is a delirious treat. It's not graphic but the implied bestiality was too much for US audiences, or more likely the MPAA. Ilona is desperately in love with Waldemar and could not possess him, hence her whole scheme to mind control Waldermar's wife and involve her in an affair. She wanted to wreck his marriage, and she accomplishes this while Waldemar is in Tibet. Unfortunately he returns a werewolf, but this does not slow her down a bit. If she can't physically have him as a man, she loves him enough to have sex with him as a werewolf. This also helps explain the later scene where the werewolf beds down with a woman he spots getting naked before bedtime while peeping through her window. This scene is presented sans nudity in the covered version and really makes no sense. In the uncut version, it would seem Ilona's affections have made the werewolf horny and in need of release, so he rapes the first woman he can after escaping. The other cut is a complete scene of Waldemar in bed with Karen and she is seen naked. A very similar bedroom scene was cut out of the US version of WEREWOLF SHADOW ( WEREWOLF VS THE VAMPIRE WOMAN ) as well. The film does have it's problems though, for certain. The director was drunk, the bad stand in for the werewolf at points, the atrocious English dubbing, the inclusion of sequences from the first Waldemar film MARK OF THE WOLFMAN aka FRANKENSTEIN'S BLOODY TERROR and the grotesque overuse of that film's music score throughout etc, but seen in it's original widescreen format and uncut ( ie: WEREWOLF NEVER SLEEPS ) it is one of the wildest and most outrageous of the Daninsky werewolf series, with a plot line unmatched in it's everything but the kitchen sink approach. The cut / clothed pan and scan full screen copies of this film do it no favors, and unfortunately that's the version almost everyone commenting on the film have seen. The film carries a 1970 copyright, and I'd bet the 1972 release date on the IMDb is incorrect. The film precedes WEREWOLF SHADOW ( aka WEREWOLF VS THE VAMPIRE WOMAN ) in the series and was certainly released before WEREWOLF SHADOW. The ending of WEREWOLF NEVER SLEEPS / FURY OF THE WOLFMAN dovetails directly into the opening of WEREWOLF SHADOW, offering concrete evidence of this. Sadly a complete version of this may never get a decent release. A perfect release would be the uncut English version but in Spanish with English subtitles. The English dubbing severely hurts the movie. But any Spanish language version would reflect the covered version as shown in Spain during the Franco era, where nudity was verboten.

...well, pop this into the DVD, waste an hour and a half of your life that you will never get back, and find out.
Acting? What acting?
Production values? ...Production? ...Values?
Story? Don't get me started.
After many years of posting on IMDb, I never thought I would see a film so bad that I truly wished for a lower rating than one. I always have found at least a reason or two to see merit - if only in the intent or the effort of the writer, the director, the cast, or the producer?
In this case, they're all the same guy (!) who really needs to get a handle on the fact, at least as demonstrated by this worthless waste of video tape, that he has no talent. I mean it would be a reasonable excuse if this were some junior high schooler's "production" for his first cinema class, but the referenced "artist" behind this dreck was twenty-six at the time of this miscarriage.
Just how did this ever get made? Who in their right mind ever wrote a check for this? Moreover, don't let the box cover fool you: there's not even anything that remotely resembles a good sex scene or any good "exposure" of the hunk on that cover.
Two final items: there was one second when this "film" had redeeming value: the aforementioned "talent" gets roundly punched out by his lover. I cheered! And, I did learn one thing from this "film.". There are times when something is so very bad that it is, indeed, truly very funny. But not in any comical manner; it's just sadly humorous. Very sadly humorous.