The subject of this study is the viral YouTube video made in 2007 of inmates of the Cebu Provincial Detention and Rehabilitation Centre in the Philippines, dancing a tribute to Michael Jackson's Thriller. The word ‘dangerous’ in the title applies to the dynamic of ‘YouTube videos like CPDRC's Thriller, with very real consequences for the inmates on the receiving end’ (p. 2). The detailed background includes a history of the Philippines and its relationship with the US, and the literature on digitised culture, which incorporates striking statistics on the growth of the YouTube phenomenon. These analyses are conducted with the force of exhaustively assembled secondary sources which suggest that the study's origins might lie in the painstakingly thorough research for a doctoral dissertation.

This is an important contribution to media studies, and I would say essential reading for specialists in the field. I want to emphasise this at the outset, because it also raises issues that I think are problematic. For me its great strength is the close engagement with a particular case study, especially in a field which is so often inclined to over-theorisation. The video under discussion was part of Prison Warden Byron Garcia's programme of rehabilitation through collective choreographed calisthenics, which he then uploaded to YouTube. The distinction between these two elements is crucial. The primary site of the programme's identification as ‘dangerous’ is the latter, ‘the most ubiquitous and public platform available in the twenty-first century’ (p. 103), a global sonic humiliating pillory. One inmate quoted says that ‘We didn't know that Mr. Byron put it on the internet and that it became so popular’ (p. 103).

As to whether the actual performance itself is also experienced as punishment, however, remains unclear. Certainly in the case of the Thriller routine, it is evidently imposed by compulsion, but as to how that is experienced, as punishment or therapeutic rehabilitation, remains largely undocumented. The latter is certainly central to Warden Byron Garcia's own stated objectives, although it is to be noted that he declined to be interviewed by the author for this study (p. 177), and while there are ‘no official reports [to] confirm exactly how the programme has healed inmates’ (p. 174), we are told that in press interviews ‘one or two sanctioned, lead-dancing inmates’ attest to the benefits of the dance programmes (p. 114). It is also telling that in Warden Garcia's early experiments in this kind of calisthenics routine, the author reports that the pop music ‘enticed inmates to singalong, clap and move together in time to the beat’. Enticement is not the same as compulsion. In the context of the generally brutal conditions of prison life as described here, it seems likely that the inmates would much prefer to have this programme than not. And while continuing to frame the calisthenics within Althussser's model of a ‘repressive state apparatus’ (p. 114), Mangaoang concedes that ‘some, if not many’ (p. 111), inmates enjoy the activity for a host of therapeutic reasons.

The distinction between the programme and its presentation as a public spectacle (as ‘prison tourism’ and on YouTube) is clearly decisive in the evaluation of its politics, but as in the instances referred to above, sometimes the distinction is blurred by the author, and I would suggest that the next stage of this valuable case study would be some investigation of post-incarceration recidivism or rehabilitation. Although ‘the authorities’ claim a reduction of recidivism, there are evidently no official figures available (p. 175). However, above all, one of the first principles of all social research is: let the subject speak. In fact the only people we really don't hear much from are the inmates themselves. Unfortunately when the author sought to conduct further follow up research, under the Duterte regime from 2016, the programme had been shut down and Garcia replaced, and access turned out to be impossible (p. 186).

She speculates that the programme ‘does little to train or educate the majority of inmates in the transferable skills needed to help them restart their lives after release’; this is a curious observation, coming as it does after citations on the value of dancing in ‘positive character formation’, which it seems to me is more ‘transferable’ than any specialised vocational training (pp. 112–13). Nor is this really consistent with the later revelation that a number (albeit a ‘modest number’) of inmates post-incarceration formed an ‘Ambassadors of Goodwill’ troupe, which now teaches dance throughout the more than 1300 detention facilities in the Philippines (p. 175).

I finish with a problem in the opening assertion of Chapter 1: ‘Music has always been mediated. Take, for example, the voice in music's modern era. The voice does not sing alone. It is accompanied by, implanted in and mediated by technologies’ (p. 19). The first problem with this is that not only is it unnecessary to the book's thesis, it is in tension with the essential distinction drawn between the actual dance practice and its YouTube mediation. In addition, I cannot see that this opening declaration is true in any useful sense. Of course all sound is mediated, if only by the air it has to pass through. However, this is not the sense which is usually communicated by ‘mediation’. Similarly the assertion that the ‘voice does not sing alone’ makes no sense to me, when in fact it often does, in the car, in the home. I spend a moment on this because it is a proposition that robs us of an important discriminator in the study of sounding. If we are going to define ‘mediation’ in a way that applies to all music, we are then deprived of an essential tool of analysis. There is a significant difference between, for example people singing/performing just for themselves (congregational hymn singing, domestic celebration singing, sportsground and political chanting), and people singing for an audience using technological mediation (see further Johnson Reference Johnson, Tsioulakis and Hytönen-Ng2017). In fact that difference is central to Mangaoang's argument. This study simply doesn't need such a statement to prosecute its important argument.